Answer:
See the answer below
Step-by-step explanation:
The independent variable would be the type of animal (horse or dog).
In the course of an experiment, the independent variable is the variable whose value does not dependent on the value of any other variable in the experiment. It is the variable that the researcher can control during the course of an experiment and whose manipulation changes or influences the actual variable the researcher is set out to measure.
I this case, if an experiment is set up to test the hypothesis that horses can swim faster than dogs, the actual variable that the experimenter would set out to measure would be the speed at which the two animals can swim. As the animals are interchanged for each other, the speed of swimming would vary.
Hence, the type of animal is the independent variable while the speed at which swimming takes place would be the dependent variable.