The answer is c. a rotation and translation
Answer:
c
Step-by-step explanation:
a. Notice that
1/(1*2) = 1/2 = 1 - 1/2
1/(2*3) = 1/6 = 1/2 - 1/3
1/(3*4) = 1/12 = 1/3 - 1/4
and so on, which suggests the n-th term of the sum can be written as

Then the sum itself is telescoping:



b. The proof is trivial:

so the formula found in (a) is correct.
28 tens would be 28 x 10 = 280
280 is the same