Answer:
The answer is below
Step-by-step explanation:
Given that:
ρ = 800 kg/m3, c = 600 J/kg-K, k = 40 W/m-K, Initial temperature = Ti = 1150,
Environment temperature = T = 450 K, Final temperature = T∞ = 325 K
Diameter = 10 mm = 0.01 m, A = 6
The estimated time for cooling process (t) is given as:

The estimated cooling time is 589 s