In a controlled experiment, the single factor manipulated by the researcher is the dependent variable and the responding factor that is measured is the
independent variable.
true or false

Zoe is investigating the composition of substance a, an unknown substance. using chemical processes, she analyzes substance a and determines it is composed of sodium, oxygen, and hydrogen atoms in a ratio of 1 : 1 : 1. what is substance a? a. a compound b. an element c. a heterogeneous mixture d. a homogeneous mixture