Can someone please help me on these I'm kind of confused

Examine the following sets of events. set a: {1, 5, 7, 9, 14} set b: {2, 5, 6, 8, 14, 17} which of the following represents the intersection of set a and set b ? {∅} {5, 14} {1, 2, 5, 6, 7, 8, 9, 14, 17} {1, 2, 6, 7, 8, 9, 17}

Which is greater, 7 p 5 or 7 c 5? 7p5 7c5

Joe has a rectangular chicken coop. the length of the coop is 4 feet less than twice the width. the area of the chicken coop is 510 square feet. what is the length of the chicken coup?