Author Question: Natural gas is: A) Heavier than air. B) Lighter than air. C) Either lighter or heavier than air ... (Read 188 times)

ashley · **on:** Jul 27, 2018

Natural gas is:

A) Heavier than air.
B) Lighter than air.
C) Either lighter or heavier than air depending on the characteristics of the local gas.
D) About the same density as air.

Question 2

Most communicating systems are wired with four wires. They are:

A) One wire for power, one for cooling, one for heating, and one for fan.
B) Two wires for 24 V power and two for communication.
C) Communication lines 1, 2, 3, and 4.
D) Power lines 1, 2, 3, and 4.