If a data value in a normal distribution has a negative z-score, which of the following must be true?
the data value must be negative.
the data value must be positive
the data value must be less than the mean.
the data value must be greater than the mean.

Amotorboat maintained a constant speed of 12 miles per hour relative to the water in going 45 miles upstream and then returning. the total time for the trip was 8.0 hours. use this information to find the speed of the current.

What is the location of maximum over the interval [-3,1.5] for the graphed function?

Arepresentative from plan 1 wants to use the graph below to sell health plans for his company. how might the graph be redrawn to emphasize the difference between the cost per doctor visit for each of the three plans? the scale on the y-axis could be changed to 0–100. the scale on the y-axis could be changed to 25–40. the interval of the y-axis could be changed to count by 5s. the interval of the y-axis could be changed to count by 20s.