Hints:
1) This is an arithmetic sequence.
2) The first member of the sequence is 4.
3) The common difference is 6. To each member, we add 6 to get the next.
4) The formula for the nth term of an arith. sequence is as follows:
l=a + (n-1)d, where l is the LAST term, n is the number of terms, d is the common difference, and a is the first term. Write this out. Play with n, increasing (integer) n until this formula predicts numbers close to 576. Do you get exactly 576 for one of these INTEGER n values? If yes, then 576 is a member of the sequence. If no, then it is not.