Answer:
B) is expanding
C) contains billions of galaxies
E) is about 10 billion years old
Explanation:
1) The universe is made of billions of galaxies, zillions of stars, and empty space.
2) The size of the universe is impossible to measure, in part because the universe is expanding.
3) Galaxies are made of clusters of stars, gas, and celestial bodies. They vary in shape and size.
4) Stars are balls of gas held together by gravity. They vary in size, temperature, and age.
