Module Quiz 7 JUVLe Question For the following questions, express your answers in three decimal places for non-whole number answers. Not yet Spot speed is defined as the instantaneous speed of a vehicle at any specified point. A standard application of a spot speed study is to answered test an increase or decrease in speed resulting from some treatment in a before and-after test. A specific road is prone to accidents and Marked out of 1.00 a researcher applied some modifications to the road to reduce the speed of the vehicles. A spot speed test was conducted before and after the modification and results are shown below. Assume that the spot speeds (mph) are normally distributed with the same standard P Flag question deviation. Use a = 0.05. Observation Before After Number 49.1 49.2 2 44.0 46.1 3 54.2 44.2 4 55 .0 53 .1 5 48.9 59.2 6 45.7 42.7 7 60.2 45.3 8 57.3 51.9 9 49 .2 51.3 10 61.5 47.3 11 39 .8 58.4 12 47 .5 49.7 13 55 .6 44.6 14 46.1 57.1 15 65.3 45.9 1. [5%] What is the standard deviation for each sample? 2. [10%] Provide appropriate null and alternative hypotheses. 3. [10%] Provide appropriate rejection criteria. 4. [50%] Determine if there is any difference in the spot speed of the vehicle before and after the road modification (provide and interpret your conclusion). 5. [25%] Find a 95% confidence interval on the difference in means for the two observations. #6 1080 acer