bootstrap aligning images

1/* used mx-auto d-block */
2
3<img class="mx-auto d-block" src="https://www.w3schools.com/bootstrap4/paris.jpg" alt="https://www.w3schools.com/bootstrap4/paris.jpg"/>
4

1Align images with the helper float classes or text alignment classes.
2block-level images can be centered using the .mx-auto margin utility class.
3
4<img src="..." class="rounded float-left" alt="...">
5<img src="..." class="rounded float-right" alt="...">
6<img src="..." class="rounded mx-auto d-block" alt="...">