Rate of change pre-calculus

I am confused how to approach this problem and need some help

The side of a cube is expanding at constant rate of 2 cm per seconds. What is instantaneous rate of change of the surface area of cube in cm^2 per seconds when its side is 3 cm?

Thanks in advance :)

A = 6s^2
dA/dt = 12s(ds/dt)
ds/dt = 2 cm/s
s = 3 cm.
dA/dt= 12 * 3 * 2 = 72 cm^2/s

You are always welcome.

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sa = a = 6x²

da/dt = 12x(dx/dt) = 12 * 3 * 2 = 72 [units]