You are conducting an experiment to determine if increased ultraviolet radiation from the decrease in
the ozone layer is killing off frog tadpoles. after examining all of the data available in the library, you
decide to go with a hypothesis that increased ultraviolet radiation from the sun is killing off the tadpoles.
you design an experiment with a control and an experimental group. group 1 involves 100 tadpoles in a
five gallon container of water, which is covered by glass (knowing that the glass will filter out the
ultraviolet radiation). group 2 will be set up exactly like group 1, except that instead of being covered
with glass, it is covered with an acrylic plexiglass, which will not filter out the u. v. radiation. you then
place the groups outside for a period of a month, and observe the results.

results
group 1 group 2
number of tadpoles 100 100
started with
number finished 96 96
using this information, answer the following questions.
a. what is the experimental variable and what is the dependant variable?
b. does the information from this experiment support the hypothesis?
c. if no, then what might be causing the decrease in frog populations?
d. which is the control group, and which is the experimental group?
e. what is the difference between the two groups? should they be
different in any other way?