Heidi is a chocolate lover and eats chocolate daily. She has a bad break-out and her friend told her eating chocolate causes pimples. Heidi continues to eat
chocolate every day for 2 weeks and counts the number of pimples she has on
her face. The following 2 weeks she doesn't eat any chocolate and counts the
number of pimples on her face.
a. Independent Variable =
b. Dependent Variable =
C. Control =

a. the weeks she ate the chocolate

b. how many pimples were on her face

c. how much chocolate she ate

(I'm pretty sure A. is right but I might be wrong)

Explanation:

a. Independent Variable = time , starting number of pimples

b. Dependent Variable = the number of pimples

C. Control =  the chocolate quantity , 2 weeks for eating and 2 weeks for chocolate fasting " The think this time equalizing is a control factor "

the answer

explanation:

the capillary tube was too close to the bottom of the beaker.

the ruler may have moved.

water got into the capillary tube.

the temperature was not allowed to equilibrate in the 2-4 minutes.