It would be C since it’s in between both inequalities and in the shaded region.
Answer:
Part a) 
Part b) 
Step-by-step explanation:
Part a) Write an equation for T (d)
Let
d ----> the number of days
T ---> the time in minutes of the treadmill
we know that
The linear equation in slope intercept form is equal to

where
m is the slope or unit rate
b is the y-intercept or initial value
In this problem we have
The slope or unit rate is

The y-intercept or initial value is

substitute

Part b) Find T (6), the minutes he will spend on the treadmill on day 6
For d=6
substitute in the equation and solve for T


Answer:
x = 6
Step-by-step explanation:
move all terms to the left:
-1.5x+12-(2.5x-12)=0
get rid of parentheses
-1.5x-2.5x+12+12=0
add all the numbers together, and all the variable.
-4x+24=0
move all terms containing x to the left, all other terms to the right
-4x=-24
x=-24/-4 - divide
x=+6
I think it is c. Hope this helps!
36.
Convert 10% to .1, (10 divided by 100)
then multiply 40 times .1
then subtract 4 by 40
=36