A mail carrier randomly inspects every 20th letter being mailed. Out of 600 letters in the sample, 3 were open. There were 18,000 letters
being mailed. Make an inference about the number of all the letters
being mailed that were open.

There is diarrhea on the floor. what do i do? my mum gonna see that i diarrhea on the floor! * don't report, i'm serious! *

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?

The graph of f(x) = |x| is transformed to g(x) = |x + 11| - 7. on which interval is the function decreasing?