Please answer correctly and without a link, thank you.

What is the mass of 4 molecules of co2

Which statement is usually true about the relationship between activation energy and reaction rates? low activation energy barriers result in low rates. high activation energy barriers result in low rates. low activation energy barriers result in no reaction. high activation energy barriers result in no reaction.

Answer asap need it by wednesday morning calculate the ph of 0.02m hcl best answer will be brainliest