1. How do astronomers refer to stars and compare their brightness? 2. How does the sky appear to move as Earth rotates?
3. What causes the seasons?
4. How can astronomical cycles affect Earth's climate?

in scientific notation, the value of the  speed of light in a vacuum

  will be written as 2.995 * 10^8. when this value is represented in the form of

  a * 10^b, then, a = 2.995 and b = 8.

the value of the speed of light in a vacuum given above can also be rounded up to approximately 300000000. in this case, the scientific notation will be written as 3 *10^8.

answerto predict;

here are some of the ways in which chemical and nuclear reactions differ.

explanation: