Just handwrite the answers and solutions very neatly. If you can print the PDF,

Just handwrite the answers and solutions very neatly. If you can print the PDF,

Just handwrite the answers and solutions very neatly. If you can print the PDF, handwrite the answers onto it with a pencil, take a picture, convert the picture into a PDF and send it back to me, that would be appreciated. Otherwise, just write the answers to each question neatly on a separate piece of paper. You could also write it on the iPad/tablet if you wish rather than a physical piece of paper. That is up to you.