By law of refraction we know that image position and object positions are related to each other by following relation

here we know that



now by above formula


so apparent depth of the bottom is seen by the observer as h = 3.39 cm
Say the initial point is (0,0)
The final point is
x = 200 + 135*cos(30) = 200 + 135*sqrt(3)/2 = 316.91 ft
y = 135*sin(30) = 135/2 = 67.5 ft
Resultant vector = (316.91, 67.5) - (0,0) = 316.91, 67.5) ft
All forces on the bullets cancel so that the net force on a bullet is zero, which means the bullet has zero acceleration and is in a state known as constant velocity. The bullet is moving at a constant value of velocity. Acceleration is the rate of velocity so having zero acceleration would mean that there is no change in velocity per unit of time.<span />
Answer:
The formula to calculate velocity in this case:
v = v0 + at
=> a = (v - v0)/t
= (50 - 0)/4
= 50/4 = 12.5 (m/s2)
Hope this helps!
:)
Starting from the angular velocity, we can calculate the tangential velocity of the stone:

Then we can calculate the angular momentum of the stone about the center of the circle, given by

where
m is the stone mass
v its tangential velocity
r is the radius of the circle, that corresponds to the length of the string.
Substituting the data of the problem, we find