Which kind of investigations allow for the control of variables? A. hypothesis

B. experimental

C. descriptive

D. comparative
(Will give brainliest to first answer)

What is a substance? a. a physical property of matter b. a chemical property of matter c. an element or compound that cannot be physically separated d. characteristics used to tell the difference between mixtures

The appropriate concentration for an iodine sanitizer is

What is the equation fort the alkaline zinc/manganese dioxide cell. a) anode b)cathode c)overall equations.