Which of the following statements is true about the carbon cycle?
carbon molecules enter the atmosphere through the process of respiration.
the carbon cycle describes how carbon moves
between living and nonliving things in the environment.
the amount of co2 in the atmosphere is increasing.
all of the above

Seltzer water is created by placing water under pressure with carbon dioxide gas. which of the following statements best describe seltzer water: a. the solution will be slightly acidic b. the solution will be slightly basic. the solution will be strongly acidic. d. the solution will be strongly basic. e. the solution will be neutral

Which statement best describes the relationship between period and frequency of light waves? a) in wave b the period increases and the frequency decreases from wave a. b) in wave a the period increases and the frequency decreases from wave b. c) in wave b the period is shorter and the frequency is greater than in wave a. d) in wave a the period is shorter and the frequency is greater than in wave b.

Classify this reaction: 2al+n2-> aln.