Answer:

Explanation:
given,
angle at which rock is thrown = 60°
rock lands at distance,d = 25 m
initial speed of rock, = ?
In horizontal direction
distance = speed x time
d = v₀ cos 60° t
25 = v₀ cos 60° t............(1)
now,
in vertical direction
displacement in vertical direction is zero
using equation of motion



putting the value of t in equation (1)

v


Hence, the initial speed of the rock is equal to 16.82 m/s
Answer:
b. horizontal distance/time graph
Explanation:
d is incorrect because object is moving at the same pace the entire time
Answer:
as we move higher altitudes force of gravity us decreases