Explanation

We are looking for the total number of cookies on this sheet, which we can get if we know the number of rows and the number of cookies in each row. On to the data statements, separately first.

Statement (1) gives the radius of a cookie. We will envision a case. If the radius is 3 inches, the diameter is 6 inches. That means that the dimensions of the metal sheet are 3 cookie diameters and 5 cookie diameters. We appear to be talking about 15 cookies. The sheet is "covered as completely as possible," because the edges of the cookies go right up to the edges of the sheet. We convince ourselves that no other case is possible. That means we have the value of nm and Statement (1) is sufficient.

Statement (2) boils down to the same thing as Statement (1). If five cookies fit exactly in 30 inches, that means they each have a diameter of 6 inches, leading back into the same case. Therefore Statement (2) is sufficient.

The correct answer is (D).