After reading a book about parrots, tani wants to learn more about them. which question could be answered through scientific investigation? which bird’s eggs taste the best? what substances make up an eggshell? which birds have the most beautiful feathers? which type of bird makes the best pet in an apartment?

I' m going to say B. WHAT SUBSTANCES MAKE UP AN EGGSHELL?

You have to look at keywords here, and the only one that refers to scientific research would be Substance.

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