I need help with this I am so confused

If a is a nonzero real number then the reciprocal of a is

Nine people are going to share a 128-ounces bottle of soda. how many ounces will each person get drink? choose the correct equation and answer for this situation

Long division setup showing an incomplete calculation. 12 is in the divisor, 6839 is in the dividend, and 5 hundreds and 6 tens is written in the quotient. 6000 is subtracted from 6839 to give 839. an unknown value represented by a box is being subtracted from 839. what number should be placed in the box to complete the division calculation?