help to solve a physic problem to solve (radiation)

An engine can be considered to have a 8 cooling fins, with an inner and outer radius of 70 mm and 80 mm respectively. If the engine has a radiation heat flow value of 1.2 kW, and the atmospheric temperature is 288K. Calculate the average fin temperature of the engine. Assume and emissivity value of 0.70.

This question has a multiple choice answer, circle only one:
a.464.9K
b.4480.86 K
c. 2250.00 K
d. 799.97 K

Original post by LaurenWilliamss

An engine can be considered to have a 8 cooling fins, with an inner and outer radius of 70 mm and 80 mm respectively. If the engine has a radiation heat flow value of 1.2 kW, and the atmospheric temperature is 288K. Calculate the average fin temperature of the engine. Assume and emissivity value of 0.70.

This question has a multiple choice answer, circle only one:
a.464.9K
b.4480.86 K
c. 2250.00 K
d. 799.97 K

By the way, what you have done so far?

It seems that there is missing info about the length of the fins and I find that the description of the fins is weird as there is an inner and outer radius.

I tagged someone who I think can help and hope he can provide some insights into this problem.