The high school band director plans to survey his students about the music he should select for their spring concert. which group would provide the best representative sample?

15 girls from all band levels
20 members of the freshman band
22 jazz band members
5 members from each of the 4 grade-level bands

Answer asap ill give ! ’ a sample of radioactive material decays over time. the number of grams, y , of the material remaining x days after the sample is discovered is given by the equation y = 10(0.5)^x. what does the number 10 represents in the equation? a. the half-life of the radioactive material, in days b. the amount of the sample, in grams, that decays each day c. the time, in days, it will take for the samples to decay completely d. the size of the sample, in grams, at the time the material was discovered

Hilary decided to purchase 3 points in order to lower her interest rate on her $140,000 mortgage. how much additional money does she need to bring to closing? a. $4200 b. $4000 c. $6 d. $400

The length of a rectangular board is 3 feet less than twice its width. a second rectangular board is such that each of its dimensions is the reciprocal of the corresponding dimensions of the first rectangular board. if the perimeter of the second board is one-fifth the perimeter of the first, what is the perimeter of the first rectangular board?