Marcus and three of his friends are guessing the radius of a circular pond. They read that the circumference is 157 ft, so they can use the equation 3.14⋅2r=157 to determine which of their guesses, which form the replacement set {20, 25, 30, 35}, is correct. What is the radius of the pond?

20 ft

25 ft

30 ft

35 ft

a function could be identified in 3 ways either on a chart,graph, or ordered pairs. first a function is that each point has its own. the rule is that there can be many x's to one y but there can not be 2 x's at different y's. so on a graph when you put a straight line through the y's there should be one dot only to be a function.

step-by-step explanation: