Answer:
a) 107.279m
b)
Explanation:
We use the second and third equations of a uniformly accelerated motion as follows;

where u is the initial velocity, v is final velocity, a is acceleration, t is time taken and s is distance covered.
Given;
u = 0m/s (since the car starts from rest)
v =40mi/h
t = 12s
a = ?
s = ?
substituting into equation (1), we obtain the following;

For the purpose of consistency of units, we have to first of all convert the 40mi/h to m/s as follows;
1 mile = 1609.34m
therefore;
40miles = 40 x 1609.34m = 64373.8m
Also,
1 hour = 60 x 60s =3600s.
Hence;

We then make sustitution into equation (2) as follows;

We then proceed to solve for s and a by solving equations (3) and (4) simultaneously.
(a) To find s, the distance covered;
from equation (3),
. We then put this into (4) to obtain the following;

b) As previously stated,
;
hence,
