A card is drawn from a well-shuffled ordinary deck of 52 cards. What is the probability that it is an ace?

Consider the following statements :

1. Two events are mutually exclusive if the occurrence of one event prevents the occurrence of the other.

2. The probability of the union of two mutually exclusive events is the sum of their individual probabilities.

Which of the above statement is/are correct?

If two fair dice are thrown, then what is the probability that the sum is neither 8 nor 9 ?

Let A and B are two mutually exclusive events with $$P(A) = {1 \over 3}$$ and $$P(B) = {1 \over 4}$$. What is the value of $$P(\overline A \cap \overline B )$$ ?