To determine which window cleaner is most effective, Thad washes half of the windows in his house with one brand and the other half with a different brand. He then compares the results to draw a conclusion about which cleaner is most effective. What kind of statistical study did Thad conduct?

A.

survey

B.

observational study

C.

theoretical study

D.

experiment

the answer for the question is D,experiment

step-by-step explanation:

once you graph it hit 2nd (the blue button) and graph

that takes you to a table of coordinates

on the left is x coordinates and on the right is y coordinates and an empty box

(you may have to scroll up/down in order to get ( x, 0)

so, converting firstly the mixed fractions to improper fractions and then "adding".