3. 1, 4, 27, 256, _____

a. 3,125

c. 2,876

c. 1,535

d. 875

4. 1, 2, 6, 24, _____

a. 40

c. 65

c. 90

d. 120

5. 1, 3, 7, 15, _____

a. 24

c. 31

c. 42

d. 56

Please kindly help. It confused me. Thanks already​