Spend time observing or thinking about events that involve matter and energy. Which events can you explain? Which events can’t you explain? Now answer the following questions.

Part A
Describe three events that you cannot explain.

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 

Because they're in different places for this the temperature varies.

The density of the block of iron is lees than the density of mercury but the density of the block of iron is greater than the density of water