The average speed of the car for the entire trip can be calculate by using:

where S is the total distance covered by the car, and t is the total time taken.
The total distance travelled by the car is:

while the total time taken is:

so, the average speed of the car is:

so, the correct answer is (3) 85 km/h.
 
        
                    
             
        
        
        
The magnitude of the vector C is 96.32m
<h3>How to solve for the magnitude of vector c</h3>
Ax = AcosθA
= 40 cOS 20
= 37.59
Ay = AsinθA
-40sin20
= -13.68
Bx = B cos θ B
= 75Cos50
= 48.21
By = BsinθB
= 75sin50
= 57.45
Cx = AX + Bx
= 37.59 + 48.21
= 85.8
Cy = Ay + By
= -13.65 + 57.45
= 43.77
The magnitude is solved by
|c| = 
= √85.8² + 43.77²
= 96.32m
The magnitude of the vector c is 96.32m
Read more on the magnitude of a vector here: 
brainly.com/question/3184914
#SPJ1
 
        
             
        
        
        
This is b. false
There are numerous ways of adjusting the forehand stroke and variations are allowed.