Fill in the blanks.
(A) The probability of an impossible event is _______________.
(B) The set of all possible outcomes of a random experiment is called the ________________.
(C) The probability of an event that is certain to happen is ________________.
(D) Tossing a fair coin has a probability of ________________ for getting heads.

(A) The probability of an impossible event is 0.

(B) The set of all possible outcomes of a random experiment is called the Sample Space.

(C) The probability of an event that is certain to happen is 1.

(D) Tossing a fair coin has a probability of $\frac{1}{2}$ for getting heads.

Concept Applied
The probability of an impossible event is $0$ and of a certain event is $1$, and the probabilities of all outcomes in a sample space add up to $1$.