An employee at a coffee shop hypothesizes that the harder the espresso grounds are tamped down into the portafilter before brewing, the longer the separation time of the heart, body, and crema will be. The accompanying data table shows the results of this experiment. The independent variable tamp measures the distance, in inches, between the espresso grounds and the top of the portafilter. The dependent variable time is the number of seconds the heart, body, and crema are separated. Complete parts (a) through (f) below