Calculate the neutron age of fission neutrons in water for the conditions given in problem 5.25.
a) 3.7 × 10⁻⁵ s
b) 2.5 × 10⁻⁷ s
c) 1.1 × 10⁻⁶ s
d) 4.8 × 10⁻⁵ s