The series consists of every second letter in the alphabet: A, C, E, G, I.

The series is in reverse alphabetical order: Z, Y, X, W, V.

This is the Fibonacci series where each number is the sum of the two preceding ones: 3+5=8.

The series consists of every second letter in the alphabet: D, F, H, J, L.

The series is the Fibonacci sequence where each number is the sum of the two preceding ones. The next number is 3 + 5 = 8.

The series consists of perfect squares: 1^2, 2^2, 3^2, 4^2. The next number is 5^2 = 25.

The series increases by 10 each time: 10, 20, 30, 40, next is 50.

The series adds 10, 10, and then 20. The next addition is 30, so 50 + 30 = 80.

The series increases by 12 each time. The next number is 48 + 12 = 60.

The differences between the numbers are 3, 5, 7, which increase by 2 each time. The next difference is 9, so 18 + 9 = 27.

The series is a geometric progression where each number is multiplied by 2. The next number is 40 * 2 = 80.

The series is a geometric progression where each number is multiplied by 2. The next number is 56 * 2 = 112.

These are prime numbers: 2, 3, 5, 7, next is 11.