Which of the following statements about motion are true? select all that apply.
a. if an object is changing direction, a force must be acting on it.
b. if an object is changing speed, a force may or may not be acting on it.
c. an object can move to the right only if a force is pushing or pulling it to the right.
d. an object that is moving through outer space far from any other objects will keep moving in a straight line indefinitely.

A, C, D

Explanation:

Newton's first law states that every object will remain at rest or in uniform motion in a straight line unless compelled to change its state by the action of an external force.

and according to Newton's 4th law: An object that is at rest will stay at rest unless a force acts upon it. An object that is in motion will not change its velocity unless a force acts upon it.

firearm identification is the process of analyzing the bullets and cartridge cases left at a crime scene to determine if they came from a particular firearm. marks on the bullets and cartridges may be common to every firearm of that type. these are called class characteristics.

causes

fossil fuels burn

cities become more industrialized

human population grows worldwide