A researcher is interested in determining whether wealth predicts happiness in college students. To find out, the researcher samples 402 students in order to conduct a regression analysis. Preliminary data analyses reveal the following: r = +.2; SSxy = 2, SSx = 10, SSy = 10. Assume that wealth and happiness were both measured on a self-report scale with possible values of 1-100 and the mean wealth value was 50 and the mean happiness value was 50. If the researcher had sampled only 42 people instead of 402, what impact would that have had on the analysis? Assume the only thing that changes is the sample size.

Asmall (but heavy) particle placed in a glass of water will follow a zigzag motion because the particle will bounce off of the water molecules it meets. this is called brownian motion. a physicist simulates this on a computer, by varying the distance a particle can travel (called the mean free length), on average, before it collides with a water molecule and assigning the change in motion to be one of 8 directions, each with a similar probability. by running the simulated particle (with the same mean free length) many times she determines that it should take 15 seconds, on average, for the particle to fall to the bottom, with a standard deviation of 1.5 seconds. next she lets a real particle fall through a glass of water and finds that it took 18 seconds. what does she conclude, and why?

After t seconds, a ball tossed in the air from the ground level reaches a height of h feet given by the equation h = 144t-16t^2. after how many seconds will the ball hit the ground before rebounding?

Abag contains pieces of paper numbered from 5 to 9. a piece of paper is drawn at random. what is the theoretical probability of drawing a number less than 8?