Why do you think surface waves are the slowest moving waves?

I will answer all of it for you.
A bridge may be defined as a structure built over a river, a dry valley, low land or an estuary or any depressed part of the land to provide a link between the two opposite sides. It is essentially a communication link on a road or railway track or a highway. Bridges especially over major rivers and in hilly and mountainous areas are very important civil engineering structures. Their role in socio-economic development and defence strategies can hardly be overemphasized. This is unlike tunnels, where alignment is primarily and essentially controlled by geological considerations. But, in the case of bridges also, the design, stability and durability depend, to a great extent, on the subsurface geological conditions that must be properly investigated and cautiously interpreted.
In any major bridge construction project, the designer is keen to place the bridge abutments and piers on as sound, strong and stable rock foundation below as possible. In most cases, if there is river bed below the water is covered by varying thickness of unconsolidated natural deposits of sand, gravels and boulders. Such loose materials are not safe as foundations for bridge piers for at least two reasons:
Firstly, piers placed directly on them would be unstable;
Secondly, the cover material is liable to be removed due to scouring by river water.
As such, the pier must be placed on stable foundation, preferably of rock, under a suitable thickness of cover material so that it is safe from scour by river water.
The height of pier from under the span to the foundation level, therefore, depends on the ‘depth of the bed rock’ below the river water.
Such sound bed rocks might be available within a depth varying from 5 to 20 meters below a river bed or they might not at all be available even up to 100 meter or more.
To achieve this, drill holes are made all along the centre line of the proposed bridge, even on the right or left of it, till they reach the sound rock sequence or up to a reasonable depth. Utmost care is needed not to mistake isolated big boulders buried underneath the river bed as the bed rock. Boulders are rocks but they are not bed rocks and cannot be trusted as foundations for bridge piers.
The very first rock encountered below the bed cover material may not be suitable as a foundation.
It should be kept in mind that three types of loads are to be borne by a bridge pier foundation:
i. The compressive, vertical loads due to the weight of the bridge span and that of pier material;
ii. The horizontal loads due to the thrust of the water flowing above as transmitted directly and through the pier;
iii. The dynamic, complex load, often inclined and shearing in character, due to heavy traffic on the bridge.
Consequently, the bed rock selected as foundation for the pier must be strong enough to bear the sum total of all these loads, not temporarily, but throughout the proposed life of the bridge.
The nature of the bed rock is commonly determined through study of petrological characters and engineering properties, especially the strength values, using the core samples obtained during drilling of test bore holes. In fact complete and very useful geological profiles could be prepared all along the centre line of the proposed bridge from the study of such core logs.
Most igneous and massive type of sedimentary and metamorphic rocks is quite strong, stable and durable as foundations for bridge piers and abutments. The group of weak rocks which might behave badly in the presence of water includes such types as cavernous limestones, chalk, friable sandstones especially with clayey cements, shales, clays, slates, schists and the layers of peat and compressible organic material.
Folding and faulting might cause some uncertainty in establishing a perfect geological profile but are not otherwise negative factors. Acute fracturing and profuse jointing is, however, undesirable at the foundation levels as these might cause settlement beyond the allowable limits.
When the bridge sites are located in the zones of seismic activity, the foundations are required to be designed for additional seismic loads as specified in the codes of respective areas.
In the glaciated areas, special care must be taken to establish the existence of drowned or buried valleys that might be filled by secondary material of most heterogeneous characters. In such cases a bed rock may be encountered only at great depth and it may be desirable to reach it through piles. Therefore the low bridge is better because;
It will cost less and be more structurally sound. The only thing is you would have to make a road down both sides of the valley but that would be more structurally efficient than trying to take the whole span of the valley on one bridge. The low bridge would also be better if there is water beneath the bridge in which is not stated.
The high bridge would cost a lot more and not be as structurally sound accordingly.

Answer:

These gases are called greenhouse gases.

Explanation:

The glass in a greenhouse has a similar effect on the Sun's rays and so it is called the Greenhouse Effect.

Answer:

meisosis I don't rember how to spell it lol. But I believe that it is the answer

Explanation:

Answer:

Explanation:

reach me at 16jacktwinwritters at g mail for more clarification

Answer:

Try time changes and start to change

Explanation:

Fermentation

Answer:

Negative Feedback Loops- dampen changes

Positive Feedback Loops- enhance changes

I hope this is what you are looking for!

Biological augmentation, bioremediation , or reforestation are names for the method.

Answer:

Non-foliated rocks have grains that are arranged randomly, and grains that do not split into layers.

Explanation:

I'm not sure what the question was asking, but I just gave phrases that described non-foliated rocks. I hope that helps?

Answer:

Empirical evidence is the information received by means of the senses, particularly by observation and documentation of patterns and behavior through experimentation. 

Empirical evidence is information that researchers generate to help uncover answers to questions that can have significant implications for our society.

Answer:

d

Explanation:

I think the answer is C. Sciences that focus on human behavior and society

Answer:

c.  Sciences that focus on human behavior and society

Explanation:

most logical answer

Answer:

Answer is D

Explanation:

Explanation:if your cell doesn’t produce enough enzymes it wouldn’t be available to speed up reactions throughout your body, and they would also not be available to make the many organelles made with proteins.

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Answer:

D

Explanation:

Lower the activation energy of vital chemical reactions, causing them to proceed too slowly

The first step in the nitrogen cycle is: Soil bacteria act to "fix" atmospheric nitrogen to form ammonia. Plants take in useful nitrogen compounds from the soil ; option C

What is the nitrogen cycle?

The nitrogen cycle refers to the processes by which nitrogen is cycled between the living and non-living components of the environment.

The nitrogen cycle is important as it helps provide plants with the useful nitrogen which they require for growth.

There are seven steps in the nitrogen cycle and they are:

nitrogen fixation,assimilation,ammonification,nitrification,denitrification,dissimilatory nitrate reduction to ammonia,anaerobic ammonia oxidation

The first step in the nitrogen cycle is nitrogen fixation which is the process by which atmospheric nitrogen is fixed into the soil by soil bacteria in a useful form required by plants. Therefore, step C occurs first.

In conclusion, the nitrogen cycle is important for plant growth.

Learn more about nitrogen cycle at: https://brainly.com/question/1380063

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Answer:

The seed of the crop absorbs the water and with sunlight, allows the crop to grow

Explanation:

Answer:

irrigation

Explanation:

irragation ; its definition is the act of adding water to crops.

Answer:

C. Genelling research

Explanation:

Not sure if it's correct but I hope this was helpful, Have a Great Day!!

Answer:

What eat next or what will turn into something next

Explanation:

Answer:

Arrow are used to show relationship between the organisms, things etc.

Answer: Ligaments and muscles

Explanation:

I said what I said

Answer: muscles and ligaments

Explanation:

Answer:

Mechanical waves

Explanation:

Mechanical waves are waves that must have a medium to transfer energy. Without a medium, mechanical waves cannot be propagated in space.

Electromagnetic waves on the other hand do not require a material medium for their propagation. They can move energy through a vacuum. Examples of mechanical waves are sound waves, water waves, seismic waves etcExamples of electromagnetic waves are x-ray, infrared, light waves.

Answer:

It would be >>O A chloroplasts

Answer:

B.)Photosynthesis removes carbon dioxide from the atmosphere, and cellular respiration puts it back.

Explanation:

One of the ways in which photosynthesis differs from respiration is that photosynthesis removes carbon dioxide from the atmosphere and cellular respiration puts it back.

Photosynthesis is the process whereby green plants manufacture their food in the presence of sunlight using carbon dioxide and water. The product is usually glucose and oxygen. Respiration breaks down energy rich compounds into ATP, carbon dioxide and water.

please provide a photo, i dont understand how this is organized

Answer: . Four to six seconds

Explanation:

Answer: A. four to six seconds

Explanation:

Explanation:

Given parameters:

Number of carabaos = 40

Area of the place = 4m²

Unknown:

Population density  = ?

Solution:

The population density of the place is the number of organisms per square km.

 Mathematically;

       Population density  = [tex]\frac{number of Carabao}{Area}[/tex]  

   Population density  = [tex]\frac{40}{4}[/tex]   = 10carabaos/m²

Answer:

solvent

Explanation:

The solvent is the substance that dissolves another thing, in this case the water dissolves the salt

Answer: Water is the solvent because it is dissolving the salt in it. Salt is the solute.

Answer:

I think this is right......

Explanation:

Enzyme activity can be affected by a variety of factors, such as temperature, pH, and concentration. Enzymes work best within specific temperature and pH ranges, and sub-optimal conditions can cause an enzyme to lose its ability to bind to a substrate.

Answer:

The silkworm is the larva or caterpillar of a silk moth. It is an economically important insect, being a primary producer of silk. A silkworm's preferred food are white mulberry leaves, though they may eat other mulberry species and even the osage orange

The silkworm is the larva or caterpillar of a silk moth. It is an economically important insect, being a primary producer of silk. A silkworm's preferred food are white mulberry leaves, though they may eat other mulberry species and even the osage orange. The moth is important because it makes silk. It is entirely dependent on humans, and it no longer lives in the wild. Silkworms eat mulberry leaves, and are native to northern China.

Answer:

ssGg goes with constricted green

ssgg goes with constricted yellow

SsGg goes with smooth green

Ssgg goes with smooth yellow

Explanation:

Answer:

c) rays give birth to live offspring, while skates lay eggs

Explanation:

Rays and skates are two species of cartilaginous fishes found in deep regions of the oceans. They are both flat shaped. In the system of classification, both organisms differ only in the order they belong to.

Rays and skates have few structural differences, however, one major difference between these two species of aquatic organisms is in their MODE OF REPRODUCTION.

- Rays have a VIVIPAROUS mode of reproduction i.e give birth to their young ones live.

- Skates have an OVIPAROUS mode of reproduction i.e. they lay fertilized eggs in cases called "mermaid's purses".

Answer:

c) rays give birth to live offspring, while skates lay eggs

Explanation:

The major difference between rays and skates is that rays give birth to live offspring (they do not lay eggs).

Also, I took the quizie :)

c should be the answer

she is correct c is the answer

Answer:

C. cellular reproduction

Answer is c.) cellular reproduction