Answer:
The rate of change of the volume of the cylinder at that instant = 
Step-by-step explanation:
Given:
Rate of increase of base of radius of base of cylinder = 7 mm/hr
Height of cylinder = 1.5 mm
Radius at a certain instant = 12 mm
To find rate of change of volume of cylinder at that instant.
Solution:
Let
represent radius of base of cylinder at any instant.
Rate of increase of base of radius of base of cylinder can be given as:

Volume of cylinder is given by:

Finding derivative of the Volume with respect to time.

Plugging in the values given:


Using 

(Answer)
Thus rate of change of the volume of the cylinder at that instant = 
She needs at least 130 points, so 130 - 75 (that she is earning from the sign up) = 65 points.
65 : 5,5 = 11,81 ≈ 12
So she has to sign up and visit he movie theatre at least 12 times to earn a movie ticket.
Answer: This may be late but the answer is C
Step-by-step explanation: You have to look at all your values and count up how many students can fit into each column of your histogram.