Can someone please answer these two questions? Isn't the first one's answer option A? I don't understand the second one. Please show steps

What is the radius of a circle with an area of 78.5 cubic inches? use 3.14 for pie

Will mark determine whether the conjecture is true or false. give a counterexample for any false conjecture. given: points r, s, and t conjecture: r, s, and t are coplanar. a) false; the points do not have to be in a straight line. b) true c) false; the points to not have to form right angles. d) false; one point may not be between the other two.

Which equation represents a line that passes through the point (9, -4) and has a slope of 3/5?