The Sanders family and the Henderson family each used their sprinklers last summer. The water output rate for the Sanders family's sprinkler was 40 L per hour. The water output rate for the Henderson family's sprinkler was 30 L per hour. The familles used their sprinklers for a combined total of 70 hours, resulting
in a total water output of 2400 L. How long was each sprinkler used?
Note that the ALEKS graphing calculator can be used to make computations easier.

d. 145*2 is 290 than the total angle is 360 then minus 290 then divide by two

yes, gavin is right.

step-by-step explanation:

gavin is correct. 

this problem is about converting 9% per year to how many percent per quarter. the rate is still the same. it only differed in the time period. so, through dimensional analysis,

9% per year  × (1 year / 4 quarters) = 2.25% per quarter

if he was asked to convert 9% per year to how many percent per quarter  compounded quarterly, then you will not simply divide by four. this is because compounding is not linear.

hope this , have a good day. c;