Thevenin equivalent circuit: (see the figure below)

Equivalent voltage source: USC =12+30 * I+(1-0.8) I *10 =12v.

Equivalent resistance: the applied voltage method is adopted to set the applied voltage u.

Then u = (1-0.8) i *10+30 * i = 32i.

So u/I = 32 ω.

So Roc = 32ωω.

Norton equivalent circuit: (see the figure below)

Short circuit output:12+30 * isc+(1-0.8) * isc = 0.

? Isc=-0.375A