Dr. toris wants to test an incentive program designed to increase attendance in her classes. for the first 8 weeks of the semester, she does not use the program and records attendance rates each week. then she institutes the incentive program for the last 8 weeks and continues to record attendance rates each week. she detects an increase in attendance over the last 8 weeks. this is an example of which experimental design?

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?

Which of the following is true about the graph of f(x)=7^x. select all that apply. a= it intercepts the x axis b=it intercepts both axis c=it intercepts neither d=it intercepts the y axis

The volume of a sphere is increased by 6%. calculate the corresponding percentage increased in it area.