1. a diagram that shows the sun at the center of the solar system is known as a? a) geocentric model. b) heliocentric model. c) universe model. d) earth moon sun model. 2. why do the planets not travel in a straight path? . a) the forces of inertia and gravity cause them to move in a elliptical orbit around the earth. b) the forces of inertia cause the planets to move in curved paths around the sun. c) the forces of inertia cause the planets to move in curved paths around the sun. d) the forces of gravity and inertia combine to produced elliptical orbits around the sun. e) all of above.

Sun at the center of the solar system is known as a 
 heliocentric model
 the model in which earth and planets revolve around the sun which is at the center
so i conclude option B is correct
hope it helps

Answertraveling around a circular trackexplanation"traveling around a circular track" is the best answer as you could be traveling around a circular track at a constant speed. your velocity would therefore have the same magnitude but will always be constantly direction. since acceleration is the rate of change of velocity, the rate of change will only involve the direction of velocity and not the magnitude.wrong choices: "an object at rest" does not accelerate at all"increasing speed while traveling around a curve" means that the acceleration will not be constant due to only change in direction; it will be constant due to both magnitude and direction"an object in free fall" does not necessarily change direction