What is the next letter in the series: B, D, F, H, __?

A. J

How many times does the letter 'E' appear in the series A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z?

A. 1

In the sequence 1, 3, 6, 10, what is the next number?

A. 15

If the sequence is A, C, E, G, what is the next letter?

B. H

In the series 2, 4, 8, 16, what is the next number?

C. 32