Which of the following is an example of a variable ratio schedule? 1, Giving a student $10 when you believe that he/she has earned "enough" A's.

2,Giving a student $10 for every A that he/she earns.

3,Giving a student $10 for any grade that he/she earns.

4,Giving a student $10 immediately after earning an A.

Write the correct abbreviation for each metric unit

You have a resistor and a capacitor of unknown values. first, you charge the capacitor and discharge it through the resistor. by monitoring the capacitor voltage on an oscilloscope, you see that the voltage decays to half its initial value in 2.70 miss . you then use the resistor and capacitor to make a low-pass filter. what is the crossover frequency fc?

The bar of prob. 5/82 is repeated here. the ends of the 0.4-m bar remain in contact with their re- spective support surfaces. end b has a velocity of 0.5 m/s and an acceleration of 0.3 m/s2 in the di- rections shown. determine the angular accelera- tion of the bar and the acceleration of end a.