Answer:
The resistance must be 6.67
Solution:
Resistance, 
Resistance, 
For the current to be the same when the switch is open or closed, the resistances must be connected in parallel as current is distributed in parallel with the same voltage across the circuit:
Thus in parallel:



Answer:
I would guess they'd probably be in an area they feel is habitatible.
The answer will be pressure.
Pressure is force per unit area.
Answer:
The reading in the scale is going to be the same, or if it experiences some change it would be minimum. The reason is because the truck will act as a big closed cage, therefore, when the pigeons fly, the air they move with their wings in order to keep flying, exerts the same force on the closed cage, that if they were standing on the ground.
If the truck however, allows the air flow, the weight might change, because under this scenario, the air flowing could represent less force exerted on the balance.
Explanation: