Missing picture in the text. I've found it here:
https://www.flickr.com/photos/
[email protected]/6791933847/in/photostream
Solution:
Circuit 1)
The three resistors are in series. So the equivalent resistance of the circuit is

So the current flowing through each resistor is the same, and it is given by Ohm's law:

And the voltage drop across each resistor is given by Ohm's law as well:



Circuit 2)
The three resistors are in parallel, so their equivalent resistance is given by


The voltage drop across each resistor is the same, and it is equal to the voltage of the battery:

while the current across each resistor is given by Ohm's law:


Answer:
F = 768 N
Explanation:
It is given that,
Speed of the elevator, v = 3.2 m/s
Grain drops into the car at the rate of 240 kg/min, 
We need to find the magnitude of force needed to keep the car moving constant speed. The relation between the momentum and the force is given by :


Since, the speed is constant,



F = 768 N
So, the magnitude of force need to keep the car is 768 N. Hence, this is the required solution.
D is the correct answer. Constructive Interference occurs when the crests of one wave overlaps with the crests of another wave. The reason it is called "constructive" is because one wave is adding energy to another wave. Hope this helps!