Question

what is the experimental group?
coconut juice
the amount of coconut juice used
water
the amount of water used
whether coconut juice or water was used
side of shower sprayed with coconut juice
side of shower sprayed with water
2 sides of the same shower are used in the experiment
the amount of slime after 3 days

Explanation:

In an experiment, the experimental group is the one that receives the treatment being tested. Here, assuming the experiment is about the effect of coconut - juice vs water on something (like slime formation in a shower), the side of the shower sprayed with coconut juice is the experimental group as it is getting the 'treatment' (coconut juice) which is different from the control (water).

Answer:

side of shower sprayed with coconut juice