Different rose bushes are grown in a greenhouse for two months. The number of flowers on each bush is counted at the end of an experiment. IV
DV
Constant

Independent Variable - The type of rose bush.

The independent variable is something you change. In a good experiment, you should only have one independent variable so things don't get confusing. In this experiment, the type of rose bush would be the independent variable. It is the one thing that is being changed.

Dependent Variable - The number of flowers.

The dependent variable is the data that is obtained in an experiment. In this experiment, the number of flowers would be the dependent variable. The amount of flowers is the data from the experiment.

Constant Variable - Soil, light, water, greenhouse, amount of time.

The constant variable is something in the experiment that stays constant and doesn't change. In this experiment, it mentioned having the timespan of two months and being in the same greenhouse, those are constants. Some other things that aren't mentioned but would be constants are the type of soil, color and amount of light, amount of water, etc.

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