Stock up on blue-ink pens and save the other ink colors for another day. You'll be more likely to stay out of legal trouble that way.

we can compare them to ordinary ballpoint pens. When light hits the ink of a blue pen, the ink reflects blue light and absorbs other colours, which is why the ink appears blue. Highlighter pens ...

Gel pens can’t be used because they don’t tend to scan well and can make it difficult to read answers. The same goes for blue ink pens. However, it’s important to keep in mind that if your ...