Law of sines/law of cosines

Based on what i know about mean, this doesn't add up.

Tracy solved the following problem. which of the statements is true? 9 ÷ 3 + 6 × 2 3 + 6 × 2 9 × 2 18 her answer is correct. her answer is incorrect. she should have multiplied before dividing. her answer is incorrect. she should have multiplied before adding. her answer is incorrect. she should have added before dividing.

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