It's about Rube Goldberg device helps pls. What was a constraint (a limitation or a condition) in this version?

Find the momentum for a 2.6-kg brick parachuting straight downward at a constant speed of 8.4 m/s .

As a car drives with its tires rolling freely without any slippage, the type of friction acting between the tires and the road is 100) a) static friction. b) kinetic friction. c) a combination of static and kinetic friction. d) neither static nor kinetic friction, but some other type of friction. e) it is impossible to tell what type of friction acts in this situation.

Aregion of space in which a measurable gravitational force is indicated by the force exerted on a test mass is called