Not enough sleep or disruptions to the sleep-wake cycle (such as those that may occur with shift work or travelling to a different time zone) cause the physiological state known as fatigue. Staying awake for 24 hours leads to a reduced hand-to-eye coordination that is similar to having a blood alcohol content of 0.1.
There are 13 hearts in a standard 52 card deck. There are also 13 diamonds, 13 spades and 13 clubs.
1 The number of ways to have one heart and two other cards is $({}_{13} C_1)({}_{39} C_2) = 13 \times 741 = 9633$. 2  We chose 1 of the 13 hearts, and two of the other 39 cards to make up the hand.