I believe that fidget toys should not be brought back in school, reason being is because fidget spinners were originally made for students with example: Autism . Who actually needed them. Now that people who don't need them are buying them and playing with them in the classroom, it causes a complete distraction and is not being used for its original purpose whatsoever .
The temperature of the Ocean affects weather conditions. Because the Gulf Stream moves warmer water from the North Atlantic towards Europe they actually have warmer winters than other areas do.
A) 
Let's start by writing the equation of the forces along the directions parallel and perpendicular to the incline:
Parallel:
(1)
where
m is the mass
g = 9.8 m/s^2 the acceleration of gravity

is the coefficient of friction
R is the normal reaction
a is the acceleration
Perpendicular:
(2)
From (2) we find

And substituting into (1)

Solving for a,

B) 5.94 m/s
We can solve this part by using the suvat equation

where
v is the final velocity
u is the initial velocity
a is the acceleration
s is the displacement
Here we have
v = ?
u = 0 (it starts from rest)

s = 8.70 m
Solving for v,

If you have a skateboard and you skate into a tree on accident the same amount of force you put onto that tree when you was on the skateboard will come back at you when you bounce back