Examples of constant :
2, 5, 0, -3, -7, 2/7, 7/9 etc.
Examples of variable :
The letters x, y, z, a, b, c, m, and n
Answer:

Step-by-step explanation:
Let x = number of books that Hannah donated
We know that the number of students is 150 and the total number of books is represented by b, we can write that as:
Average number of books donated by each student = 
Now we know that Hannah donated 3 times as much as the average. We can write that as:

Answer:
24.5
Step-by-step explanation:
Year 2000 would be 1, so year 2016 would be 17
Your equation is 1.5x - 1, and since we have x = 17, we simply plug it in:
1.5(17) - 1
25.5 - 1
24.5 is our estimated population using the line of best fit.
Answer:
A. Perpendicular
Step-by-step explanation:
When lines and/or points are in perpendicular to one another, the perpendicularity line between them measures the distance between both points and/or lines.
So to measure the distance between point c and line AB, a perpendicular line has to be drawn from c to AB or from AB to c. Either of these will arrive at the same result.
It should also be noted that the angle at the point of intersection of perpendicular lines is 90°.
10 pints = 5 quarts
4 pints = 2 quarts
6 pints = 3 quarts
2 pints = 1 quart
The Bold numbers are the ones you need to fill in.
Hope that helps :D