Photoshop :: Scaned Stuff

just scan some stuff from a page in a book.

But i wanna change the numbers in some part of it.

There are two problems

frist i don't know what font and size of the word is. But i do know it is from Ms Office

second the number are in boxes the numbers are in the same group of line and in the box but if i just remove the number by a rubber and insert number into it then people would tell that i changed it.

i want to remove the color and keep the text and the boxes.
so just make it look like a whote and black paper.

For what i know of if i use Photoshop CS3 andi sure the eyedrop to get the color of the background and the arrow it would give me the color of it and it's RGB. but if i eyedrop this how can i change the color i want to remove?

if it will remove can all the color become white the background and the arrow.

and what should i do if i want to keep the arrow?

Remeber the img is scaned not the orginal word DOC.

if i want to edit the text on the image how do i do that how do i know what font it is and how can i make the excact box? for example the first box is 1 i want make it 20 how do i do that?