of milligrams of sodium for items at a fast-food chain. Which is a correct interpretation of the slope
of the regression line?
A. Every milligram of sodium contains 0.2457 calories.
B. A food item with one more milligram of sodium than another tends to have 0.2457 more
calories.
C. A food item with one more milligram of sodium than another tends to have 136.69 more
calories.
D. A food item with one more milligram of sodium than another tends to have 147.1427 more
calories.
E. A food item with one more calorie than another tends to have 147.1427 more milligrams of
sodium.
A new fertilizer is to be tested on tomato plants to determine if it increases the production of the
plants. The available land is divided into eight plots. Four of the plots are on a hill and four are in a
valley as shown. The plots in the valley are expected to get more water due to the influence of
gravity, and those on the hill will get more direct sunlight. A randomized block design will be used,
using two blocks of four plots each. Which of the following blocking schemes would be most
appropriate?
A. Plots 1, 2, 3, and 4 in one block and plots 5, 6, 7, and 8 in the other
B. Plots 1, 2, 5, and 6 in one block and plots 3, 4, 7, and 8 in the other
C. Plots 1, 4, 5, and 8 in one block and plots 2, 3, 6, and 7 in the other
D. Plots 1, 3, 6, and 8 in one block and plots 2, 4, 5, and 7 in the other
E. The plots should be randomly assigned to blocks.
- At a large hospital, the durations of emergency room visits, from check-in to discharge, are
approximately normally distributed with a mean of 167 minutes and a standard deviation of 76
minutes. Which interval, to the nearest minute, contains the middle 80% of durations?
A. 15 minutes to 319 minutes
B. 53 minutes to 281 minutes
C. 70 minutes to 264 minutes
D. 91 minutes to 243 minutes
E. 103 minutes to 231 minutes