need some help with high school 10th grade biology stuff?

[Felf K]

yeah i need some help with this biology stuff...

1.Marta read that aloe vera promoted healing of burned tissue. she decided to investigate the effect of varying amounts of aloe vera on the regeneration of planaria (a flatworm that can regenerate itself) she bisected the planaria to obtain 10 parts (5 heads and 5 tails) for each expiermental group. she applied concentrations of 0%, 10%, 20%, and 30% aloe vera to the groups. fifteen milliliters of aloe vera solutions were applied all planaria were maintained in a growth chamber w/ identical food, temperature, and humidity. on day 15 marta observed this regeneration of the planaria parts and categorized development as full, partial, or none.

so my question is:
1.whats the manipulated variable?
2.whats the responding variable?
3.whats the 2 controlled variables?
4.Whats the experimental control (if there is one)
5.number of trials.
6.Experimental error (problems w/ the experiment).