You are conducting an experiment to evaluate how the number of hours spent exercising each week affects blood pressure. Which of the following variables would be controlled in this experiment?

Ecologist have observed a sharp increase of sulfur dioxide in the air . what might be a possible consequence of excessive sulfur dioxide in the air ? a. acid rain b. ozone layer depletion c.ozone layer hole d.increase in sea levels

S, tall stems (t) is a dominant trait while short stems (t) is a recessive trait. in a field of 1000 sunflowers, 820 are tall plants and 180 are short. which statement best describes the genotype of the sunflowers in the field?

The amount of radioactive isotopes contributing heat to earth is greater now than it was when earth was newly formed. question 20 options: true false