Is there a way to delete multiple dependencies at the same time?

Karen,

unfortunately there is no way to mass delete dependencies.  

Ariel

You can select the entire project and use the delete dependency button on the toolbar (or the keyboard shortcut Ctrl+Shift+F2). Note that you will have to expand the entire project first for this to work.

I stand corrected...  You can also do this for multiple tasks, though note it will remove all dependencies for the work items selected, so if you need to pick and choose, you'll need to do this on work item by work item level.