a. 
The equivalent resistance of a series combination of two resistors is equal to the sum of the individual resistances:

In this circuit, we have

Therefore, the equivalent resistance is

b. 5.8 V, 3.2 V
First of all, we need to determine the current flowing through each resistor, which is given by Ohm's law:

where V = 9.00 V and
. Substituting,

Now we can calculate the potential difference across each resistor by using Ohm's law again:


the most appropriate answer is A !! our mind automatically connects everything and thus make a story that we don't even familiar with in actual !!
its important so we can learn things about the species
The answer is : B. The compass will spin exactly 360 Degrees
Compass will point out to the earth's magnetic field. If we change the direction of the current , we created an effect which make the compass detect the magnetic field in the exact opposite direction, that is why it will flip exactly 180 degrees