--- title: Add a Tooltip to a D3 Element --- ## Add a Tooltip to a D3 Element ### Hint 1 Use the ` .append() ` method. ### Hint 2 Use the ` .text() ` method. ### Hint 3 Chain the ` .append() ` and ` .text() ` methods. ### Hint 4 Use a callback function in the ` .text() ` method. ### Solution Chain the following lines of code with your ` svg.selectAll("rect") ` method. ```javascript .append("title") .text(d=>d); ```