Air pollution crosswords! Someone can help? I have one crossword about air pollution to resolve, but no idea!

Observation and experimentation have led many scientists to accept a theory about the origin of the universe. this theory is called the big bang theory. scientific evidence collected and observed by scientists around the world suggests that the universe is ever expanding from a hot and dense initial state. what makes this a scientific theory? (2 points)

Anyone who's in connections academy chemistry b have the factors that affect the rate of a reaction portfolio already done?

How many moles are in 7.2 x 10^23 carbon molecules?