Answer:
20.78 m/s that we can approximate to option d (21 m/s)
Explanation:
The solution involves a lot of algebra and to be familiar with different convenient formulas for launching an object vertically under the action of gravity.
First you need to recall (or derive) the formula for the maximum height reached by an object with launches with initial velocity
:
Maximum height = 
Therefore one fourth of such height would be: 
Second, find what would be the time needed to reach that height by solving for the time in the equation for the vertical position:

And now, solve for t in the last equation using the quadratic formula to find the time needed for the object to reach that height (one fourth of the max height):

Next, use this expression for t in the equation for the velocity at any time t in the object's trajectory that comes from the definition of acceleration;

Then for the time we just found, this new equation becomes:

Now, using that the velocity at this height is 18 m/s, and solving for the unknown velocity
, we get:

Answer:
Most metamorphic processes take place deep underground, inside the earth's crust.
Explanation:
During metamorphism, protolith chemistry is mildly changed by increased temperature (heat), a type of pressure called confining pressure, and/or chemically reactive fluids. hope this helps you :)
What are you trying to say?
Answer: a. -720m/s^2
b. Yes, airbags will deploy
Explanation:
The formula for acceleration is:
= (Final velocity - Initial velocity)/Time
Final velocity = 0m/s
Initial velocity = 36m/s
Time taken = 0.05s
= (Final velocity - Initial velocity)/Time
= (0 - 36)/0.05
= -36/0.05
= -720m/s^2.
Since it's negative, it shows that there was a deceleration.
2. Yes the airbag will deploy since the acceleration gotten is more than -600 m/s^2.
The tiny ripples on the soup are not only similar to wind-generated
waves ... they ARE wind-generated waves. This is a big part of the
reason why they bear such an uncanny resemblance.