Answer:
Part a)

Part b)

Explanation:
Part a)
If block is sliding up then net force must be zero and friction will be in opposite to the direction of motion of the block


so we have





Part b)
If block is sliding down then net force must be zero and friction will be in opposite to the direction of motion of the block


so we have





Speed of car A is given as

now we need to convert it into SI units
1 miles = 1609 m
1 hour = 3600 s
now we have

now its distance from Bambi is given as

time taken by it to hit the Bambi



Now other car is moving at speed 50 mph
so its speed in SI unit will be


now its distance from Bambi is given as

as we know that 1 feet = 0.3048 m

now the time to hit the other car is


So Car B will hit the Bambi first
Answer:
Both A and D
Explanation:
Vector magnintude contains both speed and direction and so do these answer choices of 15km and 30m/s
As Potential energy =mgh
m= 0.95kg
h=3 meter
g = 9.8 m/sec^2. ( acceleration due to gravity)
So P.E =(0.95)(9.8)(3)kgm^2/s^2
P.E =27.93 joules