Answer:
a
Step-by-step explanation:
Answer:
The constant force exerted on the ball by the wall is 119.68 N.
Step-by-step explanation:
Consider the provided information.
It is given that the mass of the ball is m = 2.2 kg
The initial velocity of the ball towards left is 7.4 m/s
So the momentum of the ball when it strikes is = 
The final velocity of the ball is -6.2 m/s
So the momentum of the ball when it strikes back is = 
Thus change in moment is: 
The duration of force exerted on the ball t = 0.25 s
Therefore, the constant force exerted on the ball by the wall is:

Hence, the constant force exerted on the ball by the wall is 119.68 N.
Answer:
there are 36 girls
Step-by-step explanation:
ratio is 3 to 4
I can't see the graph but I'll try anyway
Answer:
x y
0 $20,000
1 $18,000
2 $16,200
3 $14,580
4 $13,122
5 $11,809.80
Step-by-step explanation:
We have (x + y)² = (x + y)(x + y) = x² + 2xy + y².
Let x be 3a and y be 2.5b.
Therefore (3a + 2.5b)²
= (3a)² + 2(3a)(2.5b) + (2.5b)²
= 9a² + 15ab + 6.25b².
Hence the '*' sign should be replaced with 15ab.