A student wants to design an experiment to answer the question, "How does particle size affect the rate at which particles settle out of water to form sediment on the bottom of a container?" What will be the dependent variable in the student's experiment?

The time it takes particles to form sediment on the bottom of a containers

Explanation:

The dependent variable would be the time it takes different particle sizes to settle out of water in order to form sediment on the bottom of containers.

The dependent variable is an experimental variable whose value varies according to the independent variable supplied by the researcher during the course of an experiment. The value either increases or decreases with each value of the independent variable.

In order to answer the question in the illustration, different particle sizes would have to be supplied by the student as an input - the independent variable - and the time it takes for each particle size to settle and form sediment recorded - the dependent variable.

he is very short, and he can only reach halfway up on the elevator buttons. but on a rainy day, he has his umbrella with him, and he uses it to poke the button at the top.

answer: substrate concentration. enzymes work best when there is a high enough substrate concentration for the reaction they catalyse.