If frequency is reduced by a factor of two, the wavelength will 

Acoustic impedance is 

Random variable X possesses a normal distribution with mean 50 and standard deviation 10. Random variable Y possesses a normal distribution with mean 50 and standard deviation 20. Which of the following is​ true?

A survey of Mason students was conducted. The students were asked if they were currently in a relationship and if they were involved in sports. Of those surveyed, 45% reported that they are currently in a relationship, 15% stated they are involved in sports and 10% answered yes to both survey questions. (Hint: Construct a Venn diagram). Find the probability that a randomly selected student is in a relationship or involved in sports, but not in both. 

A committee will be formed with 2 managers and 3 engineers selected without replacement from 8 managers and 12 engineers. How many different committees are possible?

Suppose a call center receives an average of 8 customer calls per hour. What is the probability that exactly 2 calls are received in the next half hour (30 minutes)?

On a multiple-choice​ exam, there are four possible answers to each of 40 questions. Each question has only one correct answer. Jane has not studied for the exam and must guess the answer to each question. (You may assume that the guesses are independent of each​ other.) The number of correct guesses that​ Jane can expect to obtain is

At a particular intersection with flashing red lights in all directions, only 5% of all drivers come to a complete stop when no other cars are visible. If an individual starts observing this intersection at a particular time, what is the probability that the 10th driver they observe under these conditions is the first to come to a complete stop?

Which of the following is least likely to indicate the need for noninvasive ventilation (NIV) in the acute care setting?

Your patient has acute pulmonary edema from left heart failure with no signs of elevated PaCO2. Which therapy should be tried first?