# Just need some help with a few questions

In school, 16 and i just need some help with a few physics questions.
my physics teacher is away so im asking here, a few of the questions i know the answers to but i do need help, and yes i know these may be easier questions than normal.

1.
A carnival machine uses two cages at the rotating arms to ensure that during the ride, the people in the cages are always in a vertical standing position. each arm is 22m long and rotates once every 9.4 seconds in a vertical circle. if the people have a mass of 50kg find:
A) person's speed
b) the net force that the cage exerts on the persons feet at the top of the circle
c) the total force the cage exerts on the person at the bottom of the circle.
These are my answers, and i cant remember how i got them
a) 14.7m/s
b) -433 newtons
c) 2506 newtons

2.
ok i had to plot a graph on a rubber stopper circuler motion experiment i did.
the graph was force(N) versus velocity(squared)
a) find the gradient of the graph and explain the units it has
NOTE: i have found the gradient so i dont understand, lol

3.
A plane flies in a vertical circle of radius 2500m. passangers in the plane feel weightlessness when the plane is at the top of the circle. (assume g=9.8m/s)
a) what is the speed of the plane in order to produce the observed effect?
b) does it matter how heavy the passangers are?

Okay these i reckon are prolly the easier questions i got, but after 4 hours of doing work my brain is a bit hurting so if anyone could help me out please? theres another harder question but it comes with a diagram so i cant ask it on here