Answer:
[tex]\large \boxed{1 \times 10^{-5}\text{ rad}}[/tex]
Explanation:
1. Number of seconds in 5 yr
[tex]\text{Time} = \text{5 yr} \times \dfrac{\text{365.25 da}}{\text{1 yr}} \times \dfrac{\text{24 h}}{\text{1 da}} \times \dfrac{\text{60 min}}{\text{1 h}}\times \dfrac{\text{60 s}}{\text{1 min}} = 1.58 \times 10^{8}\text{ s}[/tex]
2. Energy absorbed
[tex]\text{Energy} = 1.58 \times 10^{8}\text{ s} \times \dfrac{7 \times 10^{-2}\text{ dis}}{\text{1 s}} \times \dfrac{8 \times 10^{-13}\text{ J}}{\text{1 dis}} = 8.8 \times 10^{-6} \text{ J}[/tex]
3. Total radiation received
[tex]\text{Radiation} = \dfrac{8.8 \times 10^{-6} \text{ J}}{\text{78 kg}} \times \dfrac{\text{1 Gy}}{\text{1 J$\cdot$kg}^{-1}} \times \dfrac{\text{1 rad}}{\text{0.01 Gy}} = 1 \times 10^{-5} \text{ rad}\\\\\text{The average person receives $\large \boxed{\mathbf{1 \times 10^{-5}}\textbf{ rad}}$ over five rears}[/tex]
