Modify and test an HTML document from Exercise 2.9 that adds a secondlevel column label, “Tree,” and a second-level row label, “Characteristics.”

Data from exercises 2.9

Create and test an HTML document that describes a table with the following contents: The columns of the table must have the headings “Pine,” “Maple,” “Oak,” and “Fir.” The rows must have the labels “Average Height,” “Average Width,” “Typical Life Span,” and “Leaf Type.” You can make up the data cell values.