(5pts) A recent UCR graduate has been oered a job interview for his dream job. The interview is at 8:00am. If he wakes up by 6:00am he will have plenty of time to prep and arrive to the interview. To wake himself up he uses 20% of the time his phone, 45% of the time an analog radio, and 35% of the time Alexa. His past experience has shown him that he wakes up by 6:00am 80% of the time if he uses his phone, 65% of the time if he uses an analog radio and 78% of the time if he uses Alexa. (a) What is the probability that he arrived on time to the interview? (b) What is the probability that he uses Alexa to wake up given that he arrived on time to his interview