I need to know which answer is correct

If a textbook weighs 37.2 n on venus, and the book has a mass of 4.4 kg, what is the strength of gravity on venus? 8.9 m/s28.9 m/si don't have enough information,9.8 m/s2

Brutus, the dog, is pulling a bone to the left with a force of 20 n. lassie, another dog, is pulling a bone to the right with a force of 18n. what is the net force? a. b. c.

How does an observation about an object differ from an inference about that object