A space agency compiles data on​ space-shuttle launches and publishes them on its website. The following table displays a frequency distribution for the number of crew members on each shuttle mission over a​ 30-year period. Let X denote the crew size on a randomly selected shuttle from this time period. Complete parts​ (a) through​ (e) below.   Crew size 2 4 5 6 7 8     Frequency 4 5 40 20 72 1       a. What are the possible values of the random variable X​?   ​(Use a comma to separate answers as​ needed.)   b. Use​ random-variable notation to represent the event that the shuttle mission obtained has a crew size of 7. Select the correct choice below and fill in the answer box within your choice.   A.( P) B. c. Find ​P(X=4​); interpret in terms of percentages.   ​P(X=4​)= ​(Round to three decimal places as​ needed.) Interpret in terms of percentages. Select the correct choice below and fill in the answer box to complete your choice.  A. % of shuttle crews consist of at most 4 people.   B. ​% of shuttle crews consist of more than 4 people.   C.% of shuttle crews consist of exactly 4 people.

Relax! The General Social Survey asked 1719 people how many hours per day they were able to relax. The results are presented in the following table. Number of Hours Frequency 0 119 12345 192 325 262 322 240 6 146 7 44 8 Total 69 1719 Send data to Excel Consider these 1719 people to be a population. Let X be the number of hours of relaxation for a person sampled at random from this population. Submit

Tornadoes The following data represent the width (inyards) and length (in miles) of tornadoes.Width (yards), w Length (miles), L200 2.5350 4.8180 2.0300 2.5500 5.8400 4.5500 8.0800 8.0100 3.450 0.5700 9.0600 5.7Source: NOAA(a) Draw a scatter diagram of the data, treating width as theindependent variable.(b) What type of relation appears to exist between the widthand the length of tornadoes?(c) Select two points and find a linear model that containsthe points.(d) Graph the line on the scatter diagram drawn in part (b).(e) Use the linear model to predict the length of a tornadothat has a width of 450 yards.(f) Interpret the slope of the line found in part (c).

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Last school year, the student body of a local university consisted of 20% freshmen, 21% sophomores, 29% juniors, and 30% seniors. A random sample of 300 students taken from this year's student body showed the following number of students in each class. Freshmen 84 Sophomores 65 Juniors 86 Seniors 65 We are interested in determining whether there has been a significant change in the distribution of class between the last school year and this school year.If the distribution is the same as the previous year, the expected number of freshmen is _____.   a. 84     b. 87     c. 60     d. 20