Answer:
-7 (7x^2-y^2-19)
Step-by-step explanation:
Using the percentage concept, supposing 520 out of 1000 respondents believe in global warming, 52% of respondents agreed that global warming is occurring.
<h3>What is a percentage?</h3>
The percentage of an amount a over a total amount b is given by a multiplied by 100% and divided by b, that is:

In this problem, we suppose that 520 out of 1000 respondents believe in global warming, hence a = 520, b = 1000, and the percentage is of:

More can be learned about the percentage concept at brainly.com/question/10491646
Answer:
50 miles
Step-by-step explanation:
Multiply the given scale numbers by 1/2 to find your answer:
1/2 in = 100 mi
(1/2)(1/2 in) = (1/2)(100 mi) . . . . multiply the ratio values by 1/2
1/4 in = 50 mi
So 37 1/2
each can hold 2 1/2 oz
how many cups can he fill
37 1/2=75/2
2 1/2=5/2
x=number of cups
x times 5/2=75/2
5/2x=75/2
multiply both sides by 2
5x=75
divide both sides by 5
x=15
he can fill 15 cups