What is the 8th term in the following sequence 28,33,38,

To solve this, you have to figure out how they created the sequence, i.e., how did they get from 28 to 33 and then from 33 to 38 (etc.). If you subtract 28 from 33 the answer is 5, and the same is true for all the consecutive numbers in the sequence, so you have to add five to 43 to figure out the next term. You already have four terms, so we only need 4 more:
28, 33, 38, 43, 48, 53, 58, 63   63 is the 8th term.