I have a question that says: Sound is used to measure ocean depth. Sound travels 1.5 km per second through water. If it takes 3.7 seconds for a sound to reach the bottom of the ocean, how deep is the water? It is not that I can't solve the problem, I don't know the problem is asking. The only thing I know is that it multiplication. Please help me.

Scenario: susan wants to make 2 square flags to sell at a crafts fair. the fabric she wants to buy is 3 meters wide. she doesn't want any fabric left over. what's the least amount of fabric she should buy? question: which equation will susan solve her problem? note: let x represent the length of 1 side of the flag. options: 1) 2x^2 = 4x 2) 8 +2x = 2(4x) 3) 2 * 2 = 4 * 2 4) 4x^2 -2x = 0