Answer is A. first choice
Aver. 14 - 17 years old = 75/11 = 6.8
Aver. 10 - 13 years old = 47/11 = 4.27
Answer:
$156.86
Step-by-step explanation:
136.40x.15=20.46
20.46+136.40=156.86
Explanation

where x is the number of days since the start of the job
and f(x) is the rate of change
Step 1
a)find the total expenditure if the job takes 12 days
so, as x represents the number of days, just replace and calculate
let x= 12

so
a) 51.1
Step 2
now, let's find the total spent on the job from the 10 to 20th day
a) find the x value ( number of days since the job started)
x= 20 days-10dys= 10
so
x= 10
You would need to put 4 in for (n)so, 5(4)+8 then solve. 5 times 4=20 plus 8 is 28. I hope I could help!