Acid which is present in vinegar is approximately 5 % of acetic acid. This can be confirmed by testing the vinegar with magnesium which gives out hydrogen as a gas.

True, Earth is a system comprised of interacting processes. Such processes include carbon cycle, water cycle, Phosphorous cycle,...

The average propensity to consume (APC) is the ratio of consumption expenditures (C) to disposable income (DI), or APC = C / DI. 

Hence, APC = consumption/income.

RNA acts as a messenger in between the DNA and ribosome as it transforms the genetic information from the DNA and as DNA is big and can't fit into the nuclear pores.