Mrs. Green needs to store 21 math books on a shelf during school vacation. Each math book is 2.4 centimeters thick. If Mrs. Green stacks the math books on top of each other, how tall does the shelf have to be?

This is what i found “an explicit formula designates the nth term of the sequence, as an expression of n (where n = the term's location). it defines the sequence as a formula in terms of n. this example is an arithmetic sequence(the same number, 5, is added to each term to get to the next term).” i hope this you for what your looking for. can you plz mark me brainliest?