Abiology class wanted to study the effect of different materials on the melting rate of ice. they placed pieces of ice, each with a mass of 10g, onto trays. group 1 was covered in plastic, group 2 was covered in paper, group 3 was covered in aluminum, and group 4 remained uncovered. each piece of ice was allowed to melt for 15 minutes. then final mass of the ice, minus the melted water, was recorded at the end of the experiment. which of the following is the control group in this experiment? a: group 1 b: group 2 c: group 3 d: group 4

The correct answer is D: Group 4.

A control group in an experiment is a group separated from the other groups, where the variable that is being tested cannot influence the results. In this case, different materials are the independent variable that you test. Effects of that independent variable on the melting rate of ice are excluded in the control group.

the correct answer is anaphylaxis.

anaphylaxis is a condition caused by insect bites, foods, medications, manifested by tongue swelling, shortness of breath, vomiting, low blood pressure. it sometimes may occur without an obvious reason. it is treated with epinephrine injection.other tretments include antihistamines and steroids,