<h3><u>Answer</u>:- </h3>

<h3><u>Solution:-</u></h3>
<u>Given </u><u>that </u><u>:</u><u>-</u>
- job last for h hours
- Cost of job lasting more than 1 hour = $30
- Cost for the first hour = $75
Remaining hours for which the job will last after first hour= (h-1)
<u>Therefore</u>,
Cost for subsequent hours = 30×(h-1)
= 30(h-1)
Total Cost for job = Cost for 1st hour + Cost for subsequent hours

Y = mx + b
m: slope
b: y -intercept
so the y intercept is -4 or (0,-4) as a coordinate
For the first 60 positive integers, a = 1, n = 60, l = 60.
Sn = n/2(a + l)
s = 60/2(1 + 60) = 30(61)
For the next 60 positive integer, a = 61, n = 60, l = 120
Sum = 60/2(61 + 120) = 30(61 + 120) = 30(61) + 30(120) = s + 3600
Sum of first 120 positive integers = s + s + 3600 = 2s + 3600