There are 4 people at a party. if each person must shake hands with every
other person at the party exactly once, how many handshakes will there be?
(do not include units in your answer.)

6

Step-by-step explanation: So there is 4 people and lets say I'm one of them, so I shake hands with 3 people, that's 3 handshakes, then one of those 3 people shake hands with the other 2, that's 5 handshakes, and then the last 2 shake hands with each other since they haven't, so that's 1 more which means 6 handshakes.

Sorry if this is wrong.

by definition, an arc subtended by a central angle of some given measure has the same measure. so .