Answers:
a) 
b) 
c) 
Explanation:
<h3>a) Impulse delivered to the ball</h3>
According to the Impulse-Momentum theorem we have the following:
(1)
Where:
is the impulse
is the change in momentum
is the final momentum of the ball with mass
and final velocity (to the right) 
is the initial momentum of the ball with initial velocity (to the left) 
So:
(2)
(3)
(4)
(5)
<h3>b) Time </h3>
This time can be calculated by the following equations, taking into account the ball undergoes a maximum compression of approximately
:
(6)
(7)
Where:
is the acceleration
is the length the ball was compressed
is the time
Finding
from (7):
(8)
(9)
(10)
Substituting (10) in (6):
(11)
Finding
:
(12)
<h3>c) Force applied to the ball by the bat </h3>
According to Newton's second law of motion, the force
is proportional to the variation of momentum
in time
:
(13)
(14)
Finally:

We make a graphic of this problem to define the angle.
The angle we can calculate through triangle relation, that is,

With this function we should only calculate the derivate in function of c

That is the rate of change of
.
b) At this point we need only make a substitution of 0 for c in the equation previously found.

Hence we have finally the rate of change when c=0.
Answer:
She was a success.
i don't think commas are necessary because it's not a compound or complicated sentence.
The turn signal indicator should be activated at least FIVE SECONDS before merging. This is done in order to let the other drivers behind you know that you want to turn and to slow down for you, this keeps you and other road users safe and prevent accident.
Answer:
2KI + Cl₂ → 2KCl + I₂
Explanation:
The reaction equation is given as:
KI + Cl₂ → KCl + I₂
The problem at hand is to balance this chemical reaction. To solve this problem we use a mathematical approach;
aKI + bCl₂ → cKCl + dI₂
Conserving K : a = c
I : a = 2d
Cl : 2b = c
Now let a = 1, c = 1 , d =
, b =
, ;
Multiply through by 2;
a = 2, b = 1 , c = 2, d = 1
2KI + Cl₂ → 2KCl + I₂