I'm on the 3rd unit of my physics unit and we're applying Newton's 3 Laws of motion. There's this problem: "A fisherman yanks a fish out of the water with an acceleration of 4.5 m/s^2 using very light fishing line that has a "test" value of 100 N. The fisherman unfortunately loses the fish as the line snaps. What can you say about the mass of the fish?" Okay, I thought that using the F = MA formula would work, with 100=4.5 * M, which means that the mass of the fish was greater than 22 and 2/9 KG. WRONG. The answer guide I'm working from says the mass of the fish > 7.0 kg. Did I use the wrong formula? Thanks ahead of time guys.