Make a plot showing how the trip duration is related to the hour of the day. You could colour by usertype. You'll see that your plot will be compressed because of some very long durations, so only use the trips that have a duration of less than 5,000.

vega-lite_exercise 1

{
  "$schema": "https://vega.github.io/schema/vega-lite/v4.json",
  "description": "Assignment 1st graph",
  "width": 600,
  "height": "container",
  "padding": 5,

  "data": { 
    "url": "https://raw.githubusercontent.com/vda-lab/vda-lab.github.io/master/assets/station_366.json"
  },

  "transform": [
    {
      "filter": {"field": "tripduration", "lt": "5000"}
    },
    {"calculate": "hours(datum.starttime)", "as": "hour"}
  ],

  "mark": {"type": "point", "filled": true},
  "encoding": {
    "x": {"field": "hour", "type": "quantitative"},
    "y": {"field": "tripduration", "type": "quantitative"},
    "color": {"field": "usertype", "type": "nominal"}
  }
}