Please help I’ll mark you as brainliest if correct!

Answer:
a. answer choice c
b. 20301
Step-by-step explanation:
You first need to understand a formula for finding the sum of consecutive integers starting from one: (m*(m+1))/2, m is the biggest number in the set.
a. The biggest number in your set is 100, so we plug in 100 for m and solve:
100*101/2=50*101=5050
b. Same thing. Use the formula t plug in 201 for m:
201*202/2=201*101=20301
The only reason you have the picture next to your question is to prove the formula (m*(m+1))/2.