In an environmental impact study for a new airport, the noise level of various jets was measured just seconds after their wheels left the ground. The jets were either wide-bodied or narrow-bodied. The noise levels in decibels (dB) are recorded for 15 wide-bodied jets and 12 narrow-bodied jets. 'WideBodied' 'NarrowBodied' 109.5 131.4 107.3 126.8 105 114.1 117.3 126.9 105.4 108.2 113.7 122 121.7 106.9 109.2 116.3 108.1 115.5 106.4 111.6 104.6 124.5 110.5 116.2 110.9   111   112.4   a) Do the two types of jets have different mean noise levels? b) What is the name of the test used to test the hypothesis, and what assumptions are required? Test them c) Write the null and alternate hypotheses

A professor records the following final grades in one course. Construct a frequency table for the grades. B B B B C C D D F A A A A с с с с с D BD Complete the table. (Type an integer or decimal rounded to the nearest tenth as needed.) Grade Frequency Relative frequency Cumulative frequency r

Data was collected for 300 fish from the North Atlantic. The length of the fish (in mm) is summarized in the GFDT below.   Lengths (mm)      Frequency    80 - 84 1 85 - 89 16 90 - 94 71 95 - 99 108 100 - 104 83 105 - 109 18 110 - 114 3 What is the lower class limit for the fourth class?lower class limit =

The accompanying data table includes the engine size (in liters) and horsepower (HP) of 20 types of cars sold last year. Engine_Size Horsepower 3.6 246 6.2 501 6.0 435 3.4 262 3.0 258 3.5 243 3.8 321 4.0 309 4.2 362 1.4 142 1.5 124 3.6 308 1.6 155 1.8 167 5.3 422 2.0 157 2.3 185 2.4 227 2.5 183 2.8 259 (b) Estimate the linear equation using least squares. Interpret the fitted intercept and slope. Be sure to include their units. Note if either…