Answer:
cant really answer much since you need the class results for these. but i can simplify question 1. so, does the class results prove that the traits made my dominant alleles are the most common? or in other words, are traits made by dominant alleles most common in the class results?
number 4 is yes because there are more possibilities that the dominant trait will occur than the recessive trait. therefore, it is more common and the conception is correct
Oxygen and carbon dioxide travels to and from tiny air sacs in the lungs, through the walls of the capillaries, into the blood. Blood leaves the heart through the pulmonic valve, into the pulmonary artery and to the lungs.

In the experiment, the independent variable is the drug amount. Experiment group is given certain amount of drug, control group is not given the drug. The dependent variable is the body fat. I think you means the control is the living environment including food and water.
Answer: Option C.
C)the tails of plant lipids cannot pack as tightly together as animal ones
Explanation:
The tails of plant lipids cannot pack as tightly together as animal ones because the double bond in plant lipids make the hydrocarbon chains to bend making them no to pack tightly together which cause a reduction in van der Waals interaction between the fatty acids. The length of the double bond also affect the melting point of fatty acids . If the hydrocarbon chain is long, melting point will be high .