The correct answers are: amplify and brilliance.
The suffixes -fy and -ance are derivational ones which serve to change the word type. The suffix -fy will give a noun or adjective the use of a verb linked to the original idea, e.g. spot = spotify; ample = amplify. In turn, the suffix -ance will highlight the state or quality of an idea e.g. defy= defiance; brilliant = brilliance.
