1.

а = v^2 \ R

R = v^2 \ a

R = 3254^2 \ 0,281 ≈ 3,8 * 10^7 m

2.

a =  \frac{v - v0}{t}  

at = v - v0

t =  \frac{v - v0}{a}  

t =  \frac{36.5 - 25}{0.5}  = 23 \: c

3.

F = ma

a = F \ m

a = 14 \ 4 = 3,5 м\с ^2