Back to Harbor Bikes for a mixed set. Each task uses one of this unit's tools: groups, hierarchies, grand totals and subtotals, reference lines, distributions and trend lines.
Read each task twice before you start. Most of them combine a tool from this unit with something from earlier, like a count or an average, and the order of the steps matters: build the view first, then add the line, band or total on top of it.
Remember: count trips with Trip ID as Measure > Count. Reference lines are computed from the marks you see, so they change with filters, and grand totals are recomputed from the rows, not added up from the numbers in the table.