A student did an experiment to see how much candy she should use to make rock candy. She made one solution that had 3 parts sugar to one part water (3:1), and another solution that had one part sugar to one part water (1:1). She measured how many grams of candy was formed. The results are on the chart below What were the variables that the student need to control in this investigation? (check all that apply)
A. the temperature in the room
B. how hot the water was that she used
C. how much food coloring she used
D. the amount of sugar used

Radioisotopes often emit alpha particles, beta particles, or gamma rays. the distance they travel through matter increases in order from alpha to gamma. each radioisotope has a characteristic half-life, which is the time needed for half of a sample of radioisotope to undergo nuclear decay. which quality is desirable for a radioisotope that is used for medical imaging of a specific organ? check all that apply. half-life of several years half-life of several days half-life of several seconds emission of gamma rays emission of alpha particles ability to be attached to a compound used by the body ability to pass through the body without being absorbed