Please show all work and answers for each part.
Question 1) A population is normally distributed with a mean of 50 and a standard deviation of 10. What is the probability of randomly sampling this population and getting an observation of 57 or less? Give your answer as 0.XX
Question 2) Weight of a species of bird is normally distributed with a standard deviation of 2 grams. If 30% of birds weigh less than 10 grams, what is the population mean weight of these birds? Give your answer as a number without units
Question 3) For the same population as # 2 above , what is the probability of randomly sampling and getting a value between 45 and 52? Give your answer as 0.XX
Question 4) A population is normally distributed with a mean of 100 and a standard deviation of 10. For samples of size 25, what is the probability of randomly sampling and finding a sample mean of 99 or more? Give your answer as 0.XX