Experienced Excel users will appreciate that textboxes default to having a border and white background. That‘s because they are often used to add comments or guidance to a user and so have to stand out. Otherwise a user would be foolish not to type words directly into the spreadsheet‘s cells. As equations can only be created in textboxes, the default settings are somewhat different; there is no border and no fill.
This will show your Angel Investor that you indeed are a rational thinker and concerned about the money as well as the truth. If the Angel Investor cannot trust you your chances of being funded are nil. An angel investor is betting on the jockey not only the horse. As an entrepreneur you must be honest with yourself as well as your financial partner. They want to make sure you believe in what you are doing and that you also have risked your own capital, time and energies into the new business. Angel investors want you to succeed and often they also like to give their input and if you end up taking their money for your startup, the need to realize that their input needs to be taken seriously.