4. The employee with low productivity in KID company is \( 5\% \). For the employee marked as low productivity, the attendance system showed that the probability of personal leave twice in a month is \( 100\% \). In contrast, the probability of personal leave twice in a month for other employees is \( 20\% \). Mary took the personal leave twice in the last month. What is the probability that Mary is an employee with low productivity? (10%)