You need to put a picture of the graph in the question and I can answer it.
Answer:
A
Step-by-step explanation:
Sixth grade
Because if you divide their total profit by the total amount of hours they worked, you would find that the sixth grade's income per hour is the highest.
Sixth grade: 170÷5=34
Seven grade: 112÷4=28
Eighth grade: 192÷6=32
The number of situps form an AP with first term (a) = 17 and common difference (d) = 4
Tn = a + (n - 1)d
T12 = 17 + (12 - 1) x 4 = 17 + 11(4) = 17 + 44 = 61
Therefore, she will do 61 situps on day 12.
