Answer:
It does not show variation
Step-by-step explanation:
Given

Required
Determine if there's direct variation between x and y
The general form of direct variation is:

Make y the subject of formula in the given parameters;


Compare
to 
<em>Since they are not of the same form, then the given equation do not show direct variation</em>
Answer:
A, B, C all have one solution.
Step-by-step explanation:
1) Each equation in this question has one variable (x). This means that only one solution will be there.
2) Solve for x, you can cross out option D. When you subtract 52x from both sides, you're left with 52 = -78
Which is not true
3) Option A, if solved x = -65/68
4) Option B, x = 13/2
5) Option C, x = 5
All except D, have one solution, I don't know if it's a multiple choice answer but this is how I can help.
Gallons * 4
(Because there are 4 quarts in 1 gallon)
2.5 * 4 = 10.
There are 10 Quarts in 2.5 Gallons.