$1.$ Efficient combustion requires a precise balance of $\_\_\_\_\_,\_\_\_,$ and $\_\_\_\_\_$ to optimize energy output and minimize pollutants.

A$)$ fuel, oxygen, heat

B$)$ pressure, temperature, moisture

C$)$ speed, volume, density

$2.$ Fluidized bed combustion systems are favored for their ability to maintain uniform $\_\_\_\_\_,$ reduce $\_\_\_,$ and operate at $\_\_\_\_\_.$

A$)$ temperature distribution, emissions, lower temperatures

B$)$ pressure levels, fuel consumption, higher temperatures

C$)$ combustion rates, operational costs, variable temperatures

$3.$ In stoichiometry calculations, it is vital to account for the $\_\_\_\_\_$ of fuel, $\_\_\_$ required, and $\_\_\_\_\_$ produced.

A$)$ type, amount of oxygen, heat

B$)$ density, volume of air, pressure

C$)$ weight, quantity of water, light

$4.$ The major types of stokers include $\_\_\_\_\_,\_\_\_,$ and $\_\_\_\_\_,$ each suited to different industrial needs.

A$)$ chain grate, overfeed, underfeed

B$)$ electric, gas, oil

C$)$ manual, automatic, semi$-$automatic