Answer: Would be D. Fe and S have an ionic bond, while S and O have covalent.
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FOLLOWING!!!!!!!!!!!!!!!!!!!!!!!!!
Explanation:
It is known that 1 SCF produces approximately 1000 Btu of thermal energy.
As it is not mentioned for how many hours the gas is used in this process. Therefore, we assume that the total number of hours natural gas used in this process are as follows.
= 8760 hours
Now, we will calculate the annual cost of natural gas used in the process as follows.

= 555384000 SCF
Hence, annual cost of natural gas used in this process = loss of thermal energy
This will be equal to, 
= 555,384,000,000 BTU
Thus, we can conclude that the annual cost of natural gas used in the process is 555,384,000,000 BTU.
False. At equilibrium, the rate of forward reaction is equal to the rate of backward reaction. The net concentration of both products and reactants won't change, but the reactions still take place.
Benedict's solution is used to test simple sugars, such as glucose. It is blue solution, when sugar is present, it turns to orange / brick red. Depends on the concentration of sugar.