Answer:
A
Explanation:
Resistors in series add. There is only one path the current can take. That's why Christmas Tree lights sometimes give a lot of trouble. If a bulb burns out, it could be any one of them and time is needed to find the burned out bulb.
That being the case R = R1 + R2
R1 = 50 ohms
R2 = 50 ohms
R = 50 + 50
R = 100 ohms
Answer A
Answer:

Explanation:
Given: The latent heat of fusion for Aluminum is 
mass to be malted m = 0.75 Kg
Energy require to melt E = mL

Therefore, energy required to melt 0.75 Kg aluminum

Answer: Whenever two objects are touching, they usually exert forces on each other. The force of gravity, on the other hand, is an example of a force that exists between objects without them having to be in contact. Objects with mass exert forces on each other via the force of gravity.
HOPE IT HELPED:) HAVE A NICE DAY