A salesperson contacts eight potential customers per day. From past experience, we know that the probability of a potential customer making a purchase is 0.10. By using the probability distribution formula; a- What is the probability the salesperson will make exactly two sales in a day? b- What is the probability the salesperson will make at least two sales in a day? c- What percentage of days will the salesperson not make a sale? d- What is the expected number of sales per day?