Part 1 of the homework

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.5.12/d3.min.js"></script>
    <style>
      body {
        font-family: futura;
        width: 960px;
      }
      h2.title {
        color: black;
        text-align: center;
      }
      .axis {
        font-family: arial;
        font-size: 0.7em;
      }
      text {
        fill: black;
        stroke: none;
      }
      .label {
        font-size: 2em;
      }
      path {
        fill: none;
        stroke: black;
        stroke-width: 2px;
      }
      .tick {
        fill: none;
        stroke: black;
      }
      .bar {
        opacity: 0.9;
        stroke: none;
        fill: grey;
      }
      .line {
        fill: none;
        stroke: #4eb0bb;
        stroke-width: 1px;
      }
    </style>

//Call the function to pass the data.
      function draw(data) {
          "use strict";
          //debugger;
          // set margins according to Mike Bostock's margin conventions
          // https://bl.ocks.org/mbostock/3019563
          var margin = {top: 25, right: 40, bottom: 100, left: 75};
          // set height and width of chart
          var width = 960 - margin.left - margin.right,
              height = 500 - margin.top - margin.bottom;
          var barPadding = 10;
          // specify the radius of our circles and the
          // column we want to plot
          //Need this to be variable
          var field = 'Water';
        
          // Append the title for the graph
          d3.select("body")
              .append("h2")
              .text("Monthly water consumption at city of Palo Alto from yr 2009 to 2016")
              .attr('class', 'title');
          // append the SVG tag with height and width to accommodate for margins
          //mainly to get margin to correctly
          var svg = d3.select("body")
                      .append("svg")
                          .attr("width", width + margin.left + margin.right)
                          .attr("height", height + margin.top + margin.bottom)
                      .append('g')
                          .attr('class','chart')
                          .attr("transform", "translate(" + margin.left + "," + margin.top + ")");
          // remove missing values
          data = data.filter(function(d) {
            return d[field];
          });
          // bind our data to svg rects for the bar plot
          svg.selectAll(".bar")
              .data(data)
              .enter()
              .append("rect")
              // .append("circle")
                .attr('class', 'bar')
            // maximum price for rent
            var max_y = d3.max(data, function(d) {
                //debugger;
                console.log(d);
                return +d[field];
            });
            // get min/max dates
            var time_extent = d3.extent(data, function(d){
                //debugger;
                console.log(d);
                return format.parse(d['Date']);
            });
            // Create x-axis scale mapping dates -> pixels
            var time_scale = d3.time.scale()
                .range([0, width])
                .domain(time_extent);
            // Create y-axis scale mapping price -> pixels
            var measure_scale = d3.scale.linear()
                .range([height, 0])
                .domain([0, max_y]);
            // Create D3 axis object from time_scale for the x-axis
            var time_axis = d3.svg.axis()
                .scale(time_scale)
                .tickFormat(d3.time.format("%b %y"));
            // Create D3 axis object from measure_scale for the y-axis
            var measure_axis = d3.svg.axis()
                .scale(measure_scale)
                .orient("left");
            // Append SVG to page corresponding to the D3 x-axis
            svg.append('g')
                .attr('class', 'x axis')
                .attr('transform', "translate(0," + height + ")")
                .call(time_axis);
            // Append SVG to page corresponding to the D3 y-axis
            svg.append('g')
                .attr('class', 'y axis')
                .call(measure_axis);
            // add label to y-axis
            var y_label = d3.select(".y.axis")
                .append("text")
                .attr('class', 'label')
                .text("CCF (centum cubic feet)")
                    .style('font-size', '1.2em')
                .attr("transform", "rotate(-90)");
      
                // center y axis label
                y_label.attr("x", -(height / 2)).attr('y', -60)
                .style("text-anchor", "middle");
        
            // based on the data bound to each svg rect,
            // change its x, y, width, height accordingly
            d3.selectAll('.bar')
                .attr('x', function(d) {
                    return time_scale(format.parse(d['Date']));
                })
                .attr('width', function(d) {
                    return (width / data.length - barPadding)*5;
                })
                .attr('y', function(d) {
                    return measure_scale(+d[field]);
                })
                .attr('height', function(d) {
                    return height - measure_scale(+d[field]);
                });
        };
      </script>
  </head>
  <body>
    <script type="text/javascript">
    // load our data file asynchronously and pass the data
    // to the draw function once it is loaded.
    d3.csv("data.csv", draw);
    //1st argument File name
    //2nd argument call taht call back function pass all that data
    </script>
  </body>
</html>

https://cdnjs.cloudflare.com/ajax/libs/d3/3.5.12/d3.min.js