Answer:
A sphere full of air
Explanation:
because you pump it up and it is very fun to use
Answer:
Body
— Right atrium Right ventricle - Lungs – Left atrium Left ventricle -
Explanation:
A control variable is a scientific experiment in which the experimental element is unchanged throughout the experiment
a control group is a group in an experiment that does not receive the treatment by the researchers (untouched by them) and used to see the changes between the controlled group and that of the group that received the vial
hope this helps
