What is the answer to this question?

Which equations represents circles that have a diameter of 12 units and a center that lies on the y-axis? check all that apply

How many of the 250 grandparents in the population would you expect to prefer online shopping with merchant a? merchant a: 4 merchant b: 6 merchant c: 2 merchant d: 3 other: 5 none: 5 answer choices: a.about 4 b.about 8 c.about 40 d.about 21

Triangle xyz has vertices x(1,3), y(0,0)