Answer:
9
Step-by-step explanation:
B- 40 hours because 4/20 = 0.2 and 0.2*200=40
The numbers represent an arithmetic progression.
The difference between terms is d=7.
S=a1+a2+...+an, a1=3 and
an=a1+(n-1)×d=3+17×7=122
S=(a1+an)n/2=(3+122)×18/2=125×9=1125