Answer:
Its a 25% chance you choose the correct answer
Also 1/4 odds
9. 10^42
10. 59049 x 2^36
11. 12^28
12. 1.85302019 x 10^15
13. 2^11
14. 1/2
15. -1
This is not true. The infinite series

converges if and only if the sequence of its partial sums converges. The

-th partial sum is

but clearly this diverges as

gets arbitrarily large.