Answer:
A light year is the distance light travels in a year. ... And an astronomical unit is the average distance between the earth and the sun. So the distance to the sun is by definition one AU. A parsec is the distance at which one astronomical unit subtends an angle of one second of arc.
Answer:
C. a rolling bowling ball
I just answered this question on my quiz.
In physics, spacetime is any mathematical model which fuses the three dimensions of space and the one dimension of time into a single four-dimensional manifold. Spacetime diagrams can be used to visualize relativistic effects, such as why different observers perceive where and when events occur differently.
You are correct earth science is studied to predict planetery changes