Answer Happy

une ONE answer for pupu the following the ple choice questions. Each question is worth 2 points. a. In a certain county, there are three towns: A, B, and C. The household population sizes in these towns are 1000, 1500, and 2000, respectively. Assume that a random sample of 50 households is selected by simple random sampling respectively from each of the three towns so that the total sample size is 150 households. Which of the following sampling methods is used in the described example? (1) systematic sampling (2) cluster sampling (3) stratified sampling (4) convenience sampling b. Which of the following statements is TRUE? (1) A parameter is a fixed number that described the characteristic of the random sample. (2) A sample mean X denotes a biased point estimator of the population mean u. (3) A sample mean 7 is called a point estimate. (4) All of the above (5) None of the above c. Let X1 and X, denote two discrete random variables. Which of the following is always TRUE? (1) E(X1 + X2) = E(X1) + E(X2) (2) Var(X1 + X2) = Var(X1) + Var(X2) (3) SD(X1 + X2) = SD(X1) + SD(X2) (4) All of the above (5) Both (1) and (2)