Hey all. Sorry for asking so many questions about force, but these are tricky to me! Okay so I have 2 questions that I have started, but have yet to complete. Help would be greatly appreciated. 1. A model rocket weighs 5.4 N. a) What is its mass? b) What applied force makes it accelerate upward at 13.0 m/s2? Okay, so I did 5.4/9.8 to get mass which is 0.55 kg right? How do I do b? Then: 2. A space probe and rocket weigh 88,888 N. the applied force propelling the rocket is 3.0 x 106 N. Determine: a) the mass of the rocket and space probe. b) the upward acceleration of the rocket and space probe. c) the velocity of the rocket 15 seconds after lift off. So... I got a by going 88888/9.8 = 9070.20 kg I don't know what to do now.