It would be letter. b....
9x+ 5y=35
2x + 5y=0 |* -1
9x +5y= 35
-2x -5y= 0
-----------------
7x / = 35
x=35:7
x=5
2x+5y=0
2*5+5y=0
10+5y=0
5y=-10
y= -10:5
y=-2
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
A. nine hundredths
B. Thirty five hundredths
C. Seven Tenths
D. Three Thousandths
E. One Hundred Fourty five Thousandths
F. Fifty Nine Ten Thousandths
Answer is A or your first option.