2 What is the net force on an object when you combine a force of 17 N north with a force of 9 N north? Be sure to include the direction of the force.

Aflask with vinegar in it has a mass of 160 grams. a balloon with baking soda in it has a mass of 40 grams. the balloon is attached to the flask to seal the opening and the vinegar and baking soda mixes. the balloon inflates to a large volume. what will the total mass of the balloon and flask be after the balloon inflates? explain. a) less than 200 grams because the solid baking soda disappears. b) 200 grams, because all the atoms remain in the balloon or flask. c) more than 200 grams because the size of the balloon is so much larger. d) less than 200 grams because gases such as the one in the balloon are lighter than solids and liquids.

Which scientist was the first to propose the heliocentric model of the universe? a. aristotle b. isaac newton c. galileo galilei d. nicolaus copernicus

If you held a stone over the mouth of a well and then let it go , what would happen to the stone? explain your answer.