What protects living things from too much ultraviolets radiation?

If a planet rotates 360 degrees during a 24 hour time period, what does that tell us about the planet? a. the middle of the planet is in darkness b. the seasons on the planet vary every day. c. the planet runs on a 12-hour time clock. d. the temperature on the planet varies daily.

The modern periodic table has groups.

Which position represents spring in the southern hemisphere? a) b) c) d)