Answer:
Outside temperature =88.03°C
Step-by-step explanation:
Conductivity of air-soil from standard table
K=0.60 W/m-k
To find temperature we need to balance energy
Heat generation=Heat dissipation
Now find the value
We know that for sphere

Given that q=500 W
so

By solving that equation we get
=88.03°C
So outside temperature =88.03°C