In the following question, select the missing number from the given series.
19, 38, ?, 228, 684, 1368
108
113
114
138
Next Question
There are five students - P, Q, R, S and T having different heights in a class. Ps height is more than only one student. Qs height is more than S and P but not more than R. Ss height is more than P. R is not the smallest. Who is having the maximum height in the class?