Final answer:
The maximum occurrence of Co60 nuclei at 3.62 x 10^8 seconds is equivalent to about 11.46 years when the conversion factor of 3.16 x 10^7 seconds per year is applied.
Step-by-step explanation:
The maximum number of Co60 nuclei occurs at t = 3.62 x 108 seconds. To express this time in years, we can use the conversion factor that one year is equal to approximately 3.16 x 107 seconds. By dividing t by this conversion factor, we get:
t = 3.62 x 108 s / 3.16 x 107 s/year ≈ 11.46 years.
Therefore, the maximum number of Co60 nuclei occurs at about 3.62 x 108 seconds or approximately 11.46 years.