Parker is testing 2 different types of ant killer in his yard. He purchases Brand A and Brand B from the home improvement store. He applies Brand A in the front yard on Monday and Brand B in the backyard on Saturday. He then compares the ant hills on Sunday and determines that Brand A is more effective than Brand B. Why is his conclusion not valid?

Question

anonymous · Answer

He purchased 2 different types of ant killer.
 He did not say how many ant hills he had at the beginning of the test.
 He did not wait as long between each treatment of ant killer.
 He applied 1 treatment to the front yard and 1 treatment to the backyard.

nincompoop · Answer

between C and D
pick which is better way to do experiments

anonymous · Answer

i feel like it's C cause it wouldn't make sense to wait longer for one of the brands and not for the other

nincompoop · Answer

the only way to find out is to test multiple times not just one time 
there is no sufficient data to make such a conclusion