Answer:
This question is incomplete as it lacks options, the options are:
Which change would be the most effective way to improve the validity of this experiment?
A) Increase the number of goldfish in each tank.
B) Increase the daily amount of food for each tank.
C) Create another group that is fed regular fish food.
D) Increase the number of tanks in each treatment group.
The answer is C
Explanation:
According to this question, an experiment is conducted by Trey to determine which fish food causes the most goldfish activity over a period of two weeks. In this experiment, the independent variable is the FISH FOOD which are; Swift Salmon food and Fast Flounder food. Other variables such as type of gold fish, amount of fish food, amount & type of water etc.
One of the ways to improve an experiment, which is lacking in this case is to have a CONTROL GROUP. Based on the fish foods used for each group, it is obvious that all groups in this experiment are experimental. Hence, creating another group that is fed regular fish food will serve as the CONTROL GROUP in order to compare with the experimental groups. This will improve the validity of the experiment.
Geosphere, hydrosphere, atmosphere, and biosphere.
Therefore, the correct answer is D.
<h2>
A N S W E R : –</h2>
Nothing happens to the brightness of the light bulbs in the parallel circuit if the power supply is capable of supplying the additional current.
