One fair coin is tossed 25 times, let X be the number of getting heads out of those 12 tossing experiments. What is the mean and variance of X?

12 and 6.25

12.5 and 2.5

10 and 2.5

12.5 and 6.25

One fair coin is tossed 10 times, what is the probability of getting at least 8 heads out of 10 tossing experiments?

0.0439

0.0537

0.0547

0.0107