There are 20 students in the community service club. the club needs 4 officers: a president, a vice president, a secretary, and a treasurer. which expression can you use to find the number of ways to choose the officers from all of the members?

Grading scale 1 has the following weights- (tests- 50% quiz- 25% homework- 15% final exam- 10%). calculate your final average if your performance in the class is as follows-test grades- {88, 84, 90, 75, 70, 81); quiz grades- {88, 67, 90, 90, 45, 99, 76, 98, 100}; homework- 90; final exam- 75