Which of the following are true?
I. There is always a treatment in an experiment
II. An observational study is one type of experiment
III. Sample surveys are experiments
O I only
Oll only
O II and Ill only
O I and III only

What is the factored form of the following expressions? d^2 – 13d + 36

Suppose that a households monthly water bill (in dollars) is a linear function of the amount of water the household uses (in hundreds of cubic feet, hcf). when graphed, the function gives a line with slope of 1.65. if the monthly cost for 13 hcf is $46.10 what is the monthly cost for 19 hcf?

Adecorative window is made up of a rectangle with semicircles at either end. the ratio of ad to ab is 3: 2 and ab is 30 inches. what is the ratio of the area of the rectangle to the combined area of the semicircles? possible answers: a. 2: 3 b. 3: 2 c. 6: π d. 9: π e. 30: π