3.a commercial shows data that indicates when you take a certain type of cold medicine ,your cold goes away within a week. therefore, the medicine causes the cold to go away .list two or more common responses that could also cause this results. 4.a study reveals that people who exercise three times a week live longer. list two or more confounding variables that could have had an effect on this claim.

Need ! give step by step solutions on how to solve number one \frac{9-2\sqrt{3} }{12+\sqrt{3} } number two x+4=\sqrt{13x-20} number three (domain and range) f(x)=2\sqrt[3]{x} +1

The manufacturer of a new product developed the following expression to predict the monthly profit, in thousands of dollars, from sales of the productwhen it is sold at a unit price of x dollars.-0.5x^2 + 22x - 224what is represented by the zero(s) of the expression? a. the profit when the unit price is equal to 0b. the unit price(s) when the profit is equal to 0c. the profit when the unit price is greatestd. the unit price(s) when profit is greatest

Simplify. (-2)^-3 a. -8 b. -1/8 c. 1/8 d. 8