Answer:
Part A) see the explanation
Part B) 
Step-by-step explanation:
Part A)
we know that
A relationship between two variables, x, and C, represent a proportional variation if it can be expressed in the form
or 
Let
C ---> is the total cost (represent the output or dependent variable)
x ----> is the number of books (represent the input or independent variable)
In this problem
we have a proportional relationship between the variables x and C
Part B) we know that
The linear equation is given by

The constant of proportionality k is the same that the slope or unit rate of the linear equation
In this problem the constant k is given

so

For x=12 books
substitute in the equation and solve for C

In function notation

Answer:
It's B, I'm only trying my best since there is no picture.
Step-by-step explanation:
Then, he would take = $850/94 = 9.04
atleast 9.04 weeks for repaying that.......
Answer:
4.5 miles per hour
Step-by-step explanation:
Selma uses a jogging trail that runs through a park near her home. The trail is a loop that is 3/4 of a mile long. On Monday, Selma ran the loop in 1/6 of an hour. What is Selma's unit rate in miles per hour for Monday's run?
Distance = 3/4 of a mile
Time taken on Monday = 1/6 of an hour.
What is Selma's unit rate in miles per hour for Monday's run?
Unit rate in miles per hour for Monday's run = distance ÷ time taken
= 3/4 ÷ 1/6
= 3/4 × 6/1
= (3 * 6) / (4 * 1)
= 18/4
= 4.5 miles per hour
Unit rate in miles per hour for Monday's run = 4.5 miles per hour
The graph is shown in the attached image.