The main reason it's important to only test one variable at a time is so that?

a. qualitative data can be recorded

b. scientists can easily tell which variable caused the results

c. scientists can have many hypotheses tested at once

d. quantitative data can be recorded

Why reason best illustrates why hershey and chase chose to use viruses in their experiment?

Which statements describe resources? one of the factors people use when deciding where they will live is the availability of resources. renewable resources have little value for people. resources are unevenly distributed throughout the world. energy is the world resource which has the highest use. the use of nonrenewable resources has decreased in recent history. the use of resources is evenly distributed throughout the world. the world's oil supply will last for the next forty years if its use continues as expected.

Which of the following is caused by reproductive isolation within a species? a. a decrease in gene flow b. an increase in genetic flow c. a decrease in genetic drift d. an increase in gene flow