A 55-Kg Person Exposed to Thorium-234 Receives 7 $\beta$ Particles, Each with an Energy of 1

A 55-kg person exposed to thorium-234 receives 7.5 * 10⁴ $\beta$ particles, each with an energy of 1.6 *10¯¹⁴ J. How many rads does the person receive?

A) 2.1 * 10¯¹⁹
B) 1.2 * 10¯¹⁷
C) 2.2 * 10¯⁹
D) 1.2* 10¯⁹
E) None of these choices is correct.