Basic Example not working

It's not clear where the Basic Example code goes. I made a new app with create-react-app and put the example in my src/App.js but I'm getting lots of errors:

_registerComponent(...): Target container is not a DOM element.
Object../src/App.js
14 | ];
15 |
16 | // Render your table

17 | ReactDOM.render(
18 | <Table
19 | rowHeight={50}
20 | rowsCount={rows.length}