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,

Gravitational potential energy = mass x acceleration due to gravity x height
GPE=mgh
4620=mx9.81x8.4
4620/(9.81x8.4)=m=56.1 kg
the independent variables are the different
laudry detergent
the dependent variable is color of the cloth
after washing
the control variables are the amount of water
added and by washing one cloth b just water
<span>hypothesis: the cloth washed with laundry
detergent is cleaner than the cloth that is just washed by water. </span>
Answer:

Explanation:
Given data
Flight distance S=4890 km
Time difference Δt=t₂-t₁=40 min
Air speed of plane=980 km/h
To find
Speed of jet stream
Solution
When moving in the same direction as the jet stream time taken as t₁=d/(v+vs),v is velocity of plane and vs is velocity of plane
While moving in opposite direction t₂=d/(v+vs)
So

Apply quadratic formula to solve for vs
So
Hello. The answer, though I don't know what options you need to be answered, is that there is less friction between the car tires and the ice, than when they are on the road. Causing the car to slide.