What number should come next in the series: 10, 20, 30, 40, ?

B. 50

What is the next letter in the series: M, O, Q, S, ?

B. T

Find the odd one out in the series: A, C, E, G, H, I, K

B. H

What is the next number in the series: 10, 20, 30, 40, ?

B. 50

Complete the series: a, e, i, o, ?

A. U