The time spent by a financial consultant for a consultation is normally distributed with a mean of 40 min and a standard deviation of 10 min. What is the probability that for a randomly chosen financial consultancy are necessary: a) In less than 30 min? b) 30 min? c) What is the minimum time for 90% of consultancy cases.? d) By randomly choosing 5 consultancies, what is the probability that at least 2 of them are completed in less than 30 min?