During a biology lab practical, students were required to identify a metal by its density. all the metals were painted green so students could not use color as a factor to eliminate choices. carl computed the density of his sample metal to be 8.9 g/cm3. since carl's lab grade depended on his accuracy and correct identification of the sample metal, he was unsure which sample he had, nickel or copper.

Group control group #1 experimental group yes yes yes control group #2 no new drug orange juice bed rest no yes no yes ves which of the following is the best explanation of why a second control group was included in this experiment? o a. to provide the volunteers in the study with something to drink o b. to prove that the common cold cannot be cured c. to confuse anyone who is trying to steal their new drug and sell it as their own invention o d. to researchers conclude that results are related to the new drug and not to the orange juice submit e previous