Answer:

Explanation:
To find Depth D of lake we must need to find the time taken to hit the water.So we use equation of simple motion as:
Δx=vit+(1/2)at²

As we have find the time taken now we need to find the final velocity vf from below equation as

So the depth of lake is given by:
first we need to find total time as
t=3.0-1.01 =1.99 s

Answer:D
Explanation:
It was right o khan academy
Answer:
94.67 N
Explanation:
Consider a free body diagram with force, F of 41 N applied at an angle of 37 degrees while the weight acts downwards. Resolving the force into vertical and horizontal components, we obtain a free body diagram attached.
At equilibrium, normal reaction is equal to the sum of the weight and the vertical component of the force applied. Applying the condition of equilibrium along the vertical direction.

Substituting 70 N for W, 41 N for F and
for 37 degrees
N=70+41sin37=94.67441595 N and rounding off to 2 decimal places
N=94.67 N
D , the e ecosystem would take years to fully restore