Of the items manufactured by a certain process, 20% are

Classical Mechanics 0
Consider an arbitrary rigid body with an axis of rotational symmetry, which we'll call i. (a) Prove that the axis of symmetry is a principal axis. (b) Prove that any two directions x and Sr perpendicular to i and each other are also principal axes. (c) Prove that the principal moments corresponding t

Myers' Psychology for AP 2
Dr. Tabor wanted to investigate the relationship between sleep and levels of alertness during a class for American university students. She gave surveys to 150 college freshmen in her introduction to psychology course, asking them to report how many hours they slept each night during a two-week perio

Physical Chemistry 8
A vessel of volume \(22.4\mathrm{\ dm}^3\) contains \(1.5\mathrm{\ mol}\mathrm{\ H}_2\) and \(2.5\mathrm{\ mol}\mathrm{\ N}_2\) at \(273.15\mathrm{\ K}\). Calculate (a) the mole fractions of each component, (b) their partial pressures, and (c) their total pressure.

Principles of Economics 6
The New York Times reported (Feb. 17, 1996) that subway ridership declined after a fare increase: There were nearly four million fewer riders in December 1995, the first full month after the price of a token increased 25 cents to $1.50, than in the previous December, a 4.3 percent decline. a. Use the

Biology for AP Courses
Apoptosis can occur in a cell under what conditions? a. when a cell is infected by a virus b. when a cell is damaged c. when a cell is no longer needed d. all of the above

Plant Systematics 3
Describe the example of Caytonia and glossopterids as putative angiosperm progenitors, citing evidence for or against this idea

Principles of Economics 9
Which of the following is an example of a positive externality? a. Dev mows Myras lawn and is paid $100 for the service. b. Devs lawnmower emits smoke that Myras neighbor Xavier has to breathe. c. Myras newly cut lawn makes her neighborhood more attractive. d. Myras neighbor Xavier offers to pay her