(1) 2, 4, 6, 8, …….
Answer: All are numbers
(2) 2, 3, 5, 7, 11, …….
Answer: All are numbers
(3) 1, 4, 9, 16, …….
Answer: All are squares
(4) January, February, March, April,…
Answer: All are English
(5) Thumb, index finger, middle finger, ring finger, pinky.
Answer: All are of a hand