A study of king penguins looked for a relationship between how deep the penguins dive to seek food and how long they stay underwater. For all but the shallowest dives, there is a linear relationship that is different for different penguins. The study report gives a scatterplot for one penguin titled " The relation of dive duration (DD) to depth (D)." Duration DD is measured in minutes and depth D is in meters. The report then says, " The regression equation for this bird is: DD = 2.2 + 0.0086 D.

(a) What is the slope of the regression line?.
    ANSWER   minutes per meter.

(b) According to the regression line, how long does a typical dive to a depth of 150 meters last?
    ANSWER   minutes.