Explanation:
Option 1.
4y=12
Dividing 4 both sides
y=3
Division property should be used.
Option 2.

Cross multiplying each other,
y=12(4)
y=48
Option 3.
2(4y)=12
Opening bracktet in LHS
8y=12
Dividing both sides by 8 i.e.

Division property is used.
Option 4.
y+4=12
Subtracting both sides by 4 i.e.
Y+4-4=12-4
y=8
Subtraction property is used.
<em><u>It means that in option (4) Soo-Jung used the subtraction property of equality to solve an equation for y.</u></em>
Do you want the definition ?
Answer:
Black carbon, tropospheric ozone, methane, and hydrofluorocarbons (HFCs) are all considered short-lived climate pollutants (SLCPs). Because these pollutants have atmospheric lifetimes of only days to a decade and a half (compared to CO2 which can persist in the atmosphere for millennia) they are referred to as short-lived climate pollutants.
Explanation: