Answer:
<em>Gravitational</em><em> force</em>
Explanation:
............
Answer:
She must be launched with minimum speed of <u>57.67 m/s</u> to clear the 520 m gap.
Step-by-step explanation:
Given:
The angle of projection of the projectile is,
°
Range of the projectile is,
m.
Acceleration due to gravity, 
The minimum speed to cross the gap is the initial speed of the projectile and can be determined using the formula for range of projectile.
The range of projectile is given as:

Plug in all the given values and solve for minimum speed,
.

Therefore, she must be launched with minimum speed of 57.67 m/s to clear the 520 m gap.
<span>An angle of refraction is the angle between the refracted ray and the "Normal ray"
Hope this helps!</span>
Answer:20/47 meter per second
Explanation:
Mass of arrow(ma)=0.25kg
Velocity of arrow(va)=12m/s
Mass of target(mt)=6.8kg
Velocity of target(vt)=0 since target is at rest
Conservation of linear momentum says that :
maxva+mtxvt=(ma+mt)V
V=(maxva+mtxvt)/(ma+mt)
V=(0.25x12+6.8x0)/(0.25+6.8)
V=3/(7.05)
V=20/47 meter per second
I think WA in friction means Water Absorption.