Answer:
B. 50
Step-by-step explanation:
5^2 +7*3 +4 = 25+21+4
= 25+25
= 50
ANSWER

EXPLANATION
The average velocity of the ball is the rateof displacement over the total time.
The height of the ball, in feet, after t seconds is given by the function:

At time t=1, the height of the ball is


At time t=6, the height of the ball is



The average velocity




Yesterday's price of notebook = $3.45
Today's price of notebook = $3.20
We have to determine the percentage decrease in the cost of notebook.
Percentage decrease = (Decrease
Old price) 
So, percentage decrease = 
=
= 7.246%
= 7.25%
Therefore, there is 7.25% of decrease in the cost of the notebook.