Students of different grades were given the same jigsaw puzzle to assemble. The time they took to assemble it was measured. What is the dependent variable? What is the independent variable? What is the control variable?

Brian has a medical condition called cone dystrophy, which is a disorder of the cone cells in the eye. what symptoms would you expect brian to have? a. inability to see in the dark b. difficulty determining colors c. difficulty determining shapes and outlines d. inability to see in all light conditions