Dragging row edge with the mouse to set height manually:
See also Column Widths
Double clicking row edge to set height automatically:
Using the context menu (right click) to set the height manually:
Using the ribbon menu to set the height manually:
Setting the height of multiple rows at the same time:
Selecting non-adjacent columns, rows and cells all work in the same manner. Hold the Ctrl key down and click on each of the items you want to select.