绘制一张柱状图，显示每个季度的销售额。
销售数据: 
{"一季度": 20000, "二季度": 35000, "三季度": 42000, "四季度": 55000}
Sorry, I cannot create visual content as I am a text-based program. However, the instructions for creating a bar chart for sales data are as follows:

1. Choose an appropriate tool such as Excel or Google Sheets.
2. Enter the sales data into a spreadsheet.
3. Highlight the data and then select the "Insert Chart" option.
4. Choose a bar chart type from the chart options.
5. Customize the chart by adding titles, axis labels, and formatting as desired.