Please help answer this question

Microorganisms are involved in each of the following processes excepta. smog production. b. food production. c. infection. d. o2 production. e. decomposition of organic material.

Suggest why placing wheels under a heavy box reduces the neccessary force required to push it along at a constant speed.

What type of organism is a one-celled organism that functions as a single unit? a. bi-celled b. single-celled c. pre-celled d. multi-celled