We have two urns. Urn 1 has 2 red balls and 3 yellow balls, while Urn 2 has 3 red balls and 7 yellow balls. We randomly select 75 balls form Urn 1, sampling with replacement. We independently randomly select 100 balls from Urn 2, sampling with replacement. Find the variance of the random variable defined as the number of red balls obtained from Urn 2 less the number of red balls obtained from Urn 1.

What is the value of x divided into y - z if x = 32, y = 4, and z = 2 3/4?

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?

Brent needs to paint a logo made using two right triangles. the dimensions of the logo are shown below. what is the difference between the area of the large triangle and the area of the small triangle? (1 point) select one: a. 4.5 cm2 b. 8.5 cm2 c. 16.5 cm2 d. 33.0 cm2