2. Which of the following is NOT true of carbon levels in Earth's atmosphere?
A. The composition of Earth's atmosphere has changed drastically over
time.
B. Drastic changes to the temperature of Earth's surface have
happened as a result of changes in the atmosphere's carbon levels.
C. Mass extinctions have occurred as a result of changes to the
atmosphere's carbon levels.
D. It is impossible to significantly change the carbon levels in Earth's
atmosphere.

Long term exposure to waves can cause sunburns and skin cancer. a) visible b) infrared c) gamma rays d) ultraviole

If we compare and contrast electromagnetic waves with sound waves, all but one statement is true. that is a) sound waves require a medium to travel while electromagnetic waves do not. b) electromagnetic waves can travel through the vacuum of space while sound waves cannot. c) electromagnetic waves must have a medium in which to travel, but sound waves can travel anywhere. eliminate d) sound waves must bounce off of matter in order to travel while electromagnetic waves do not require matter to be present.

Click the button that shows the correct relationship of the electron affinities of the elements sodium and phosphorus. sodium’s electron affinity value is more negative than the electron affinity value of phosphorus. phosphorus’ electron affinity value is more negative than the electron affinity value of sodium. this information cannot be determined using the periodic table. answer is b on e2020.