(PLEASE HELP) Which of the following describes an element?

A. Matter made up of only one type of atom
B. A substance made of two or more types of atoms
C. Two or more types of atoms chemically bonded together
D. Two or more types of atoms that are not chemically bonded

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 

The answer is that they are composed mostly of liquid water.