Astronomers estimate that as many as 100 billion stars in the milky way galaxy are encircled by planets. if so, we may have a plethora of cosmic neighbors. let p denote the probability that any such solar system contains intelligent life. how small can p be and still give a 50-50 chance that we are not alone?

Water flows at a steady rate from a tap. its takes 40 seconds to fill a 4 litre watering can from the tap. the rate at which water flows from the tap is halved. complete: 4 litres into cm3

45% of the trees in a park are apple trees. there are 27 apple trees in the park. how many trees are in the park in all?

The weekly amount spent by a company for travel has an approximately normal distribution with mean = $550 and standard deviation = $40. a) what is the probability that the actual weekly expense will exceed $570 for more than 20 weeks during the next year? (note: one year = 52 weeks) b) what is the probability that actual weekly expenses exceed $580 for 10 or more, but 16 or fewer weeks during the next year?