To find the circumference of a round object, you will take the diameter and multiply is by pi to get 78.5mm
Answer: x=-10, y=13
Step-by-step explanation:

+2y-2y = 0, eliminating y is much easier. So -3x-5x = -8x and 56+24 = 80

Substitute x in any equations but only 1 equation (Don't substitute in both equations.)
For me, I'd substitute x in -3x+2y=50

So the answer is x = -10, y = 13
You already have the right Answer which is b
Answer:
The situation you are describing can be written as y=2x, or in this case t=2f, for every fragrance purchased there are 2 ounces of lotion that are given. Since the ounces of fragrance are not shown in this question, we can only make the graph on the ounces of lotion for every fragarance purchased. The points of the graph represent that for every fragrance bought, there is twice the amount of that in ounces of lotion. In summary, the rule is t=2f where t would equal purchases of fragrance and f would equal the ounces of lotion.
(If there is any more you would like to add to the question I can answer that.)
Form the ratio 560/2800 and then mult. the result by 100%:
560
--------- * 100% = 20%
2800