The normal Acrobat Reader DC is the free version of the program and will not be able to edit PDFs for you in this manner.

You may use your RISD Acrobat DC subscription to edit images or objects in a PDF.

You will need to sign into your RISD Adobe CC subscription to do so. 

Adobe Creative Cloud (Students)

Adobe Creative Cloud (Faculty and Staff / CE Instructors)

Solution: 

Easily rotate, flip, crop, clip, move, resize, or replace an image or object in a PDF using Acrobat DC. 

Reference this link for these instructions and more.