Well the difference between velocity and speed would be that velocity is basically speed with a direction with a vector assisting with it... and Speed would be distance traveled... I hoped that this helped. :)<span />
Answer:

Explanation:
R = Horizontal range of projectile = 75 m
v = Velocity of projectile = 37 m/s
g = Acceleration due to gravity = 
Horizontal range is given by

The angle at which the arrow is to be released is
.
Answer:
0.5A
Explanation:
Using
,
R is the resistance (in Ohms)
V is the voltage (in V)
I is the current (in A)

I = 0.5A
Answer:
304 meters downstream
Explanation:
The given parameters are;
The speed of the swimmer = 2.00 m/s
The width of the river = 73.0 m
The speed of the river = 8.00 m/s
Therefore;
The direction of the swimmer's resultant velocity = tan⁻¹(8/2) ≈ 75.96° downstream
The distance downstream the swimmer will reach the opposite shore = 4 × 73 = 304 m downstream
The distance downstream the swimmer will reach the opposite shore = 304 m downstream
it is true. the trajectory reaches the value of zero at the top