Answer:

Explanation:
Given:
mass of first particle, 
mass of second particle, 
mass of third particle, 
coordinate position of first particle in meters, 
coordinate position of second particle in meters, 
coordinate position of third particle in meters, 
<u>Now, gravitational force on particle 3 due to particle 1:</u>



towards positive Y axis.
<u>gravitational force on particle 3 due to particle 2:</u>



towards positive X axis.
<u>Now the net force</u>



<em>For angle in counterclockwise direction from the +x-axis</em>

The centripetal force is:
F = mv² / R
Where:
m: mass of the object
v: object speed
R: radius of the curve.
We have to:
m = 2000kg
v = 25 m / s
R = 80 meters.
Then the centripetal force acting on the vehicle is:
F = (2000kg * (25m / s) ²) / 80m
F = 15625 N
Answer:
It's a pretty simple suvat linear projectile motion question, using the following equation and plugging in your values it's a pretty trivial calculation.
V^2=U^2+2*a*x
V=0 (as it is at max height)
U=30ms^-1 (initial speed)
a=-g /-9.8ms^-2 (as it is moving against gravity)
x is the variable you want to calculate (height)
0=30^2+2*(-9.8)*x
x=-30^2/2*-9.8
x=45.92m