Answer: mechanical cleaning
Explanation:Mechanical cleaning involves the use of sandpaper, abrasives, or other cleaning devices. This implies that large quantities of chemical solvents are not used.
We have the expression <u>12h+30w</u> to represent an employees salary.
h represents the number of <u>hours worked</u>
w represents the number of <u>wagons sold</u>
<u />
To find the answer, simply insert the numbers given where their corresponding variables are in the expression.
12(6 hours) + 30(3 wagons)
(12*6) + (30*3)
72 + 90 = 162
So the employee earns $162
