Two independent random samples have been selected. 100 observations from population 1 and 100 from population 2. sample means ¯x_1=70 and ¯x_2=50 were obtained. from previous experience with these populations, it is known that the variances are σ_1^2=100 and σ_2^2=64. determine the rejection region for the test of h_0: μ_1-μ_2=5 vs h_a: μ_1-μ_2≠5 using α=0.05. (a) z > 1.96 (b) z < -1.96 (c) z < -1.96 and z > 1.96 (d) z < -1.645 and z > 1.645

If a baseball player hits a baseball from 4 feet off the ground with an initial velocity of 64 feet per second, how long will it take the baseball to hit the ground? use the equation h = −16t2 + 64t + 4.

When turned about its axis of rotation, which shape could have created this three-dimensional object?

Martha has a deck of cards. she has lost some of the cards, and now the deck only contains nine spades, eleven diamonds, eight clubs, and twelve hearts. martha predicts that whenever she draws a card from the deck without looking, she will draw a club one-fifth of the time. which activity would best allow martha to test her prediction? a. randomly draw a card from the box and see if it is a club. b. randomly draw a card. then, continue to draw another card until all eight clubs are drawn. c. randomly draw and replace a card 120 times. then, observe how close to 30 times a club is drawn. d. randomly draw and replace a card 100 times. then, observe how close to 20 times a club is drawn.