In an experiment, a scientist decides to study the effect of exercise on cholesterol levels in people. he studies two set of people—those who exercise every day for an hour and those who don’t exercise at all. in this case, the statement that people who exercise for an hour may have lower cholesterol levels is . to test this statement, the scientist would measure cholesterol levels in exercisers and non-exercisers. the cholesterol levels would be

In the mentioned case, the statement that people who exercise for an hour may have lower levels of cholesterol is a hypothesis, and the cholesterol levels in the experiment would be the dependent variable.

Explanation:

A hypothesis is a suggested statement, that is, based upon the previous information, and is used as an initiation point in a scientific investigation.  

Any scientific experiments comprise two variables, that is, dependent and independent variables. The independent variable refers to the variable, which is controlled or modified in a scientific experiment in order to determine its influence on the dependent variable.  

I just took the test

Explanation:

Here is the answer

answer; ///(b) it is composed of four protein chains and four heme groups;

well, that's easy; the answer's c, "it reduces contamination of the water and substrate of the estuary."