C. Electrical conductivity, that means it can pass electricity through wires if needed, think of your phone charger as an example
Light does not travel at a constant speed in a vacuum, compared to in air, because the light is being absorbed by atoms and molecules in the air. But light does travel at a constant speed in a vacuum.
So I agree with A
All that talk about moving forward is irrelevant (I think)
The first question's answer is
Answer:
Option d. 2615.0g
Explanation:
Let M1, M2, and M3 represent the masses of the three different samples
M1 = 0.1568934 kg = 156.8934g
M2 = 1.215mg = 1.215x10^-3 = 0.001215g
M3 = 2458.1g
Total Mass = M1 + M2 + M3
Total Mass = 156.8934 + 0.001215 + 2458.1
Total Mass = 2614.994651g
Total Mass = 2615.0g