Answer: 20
Step-by-step explanation: Hello! The first thing you have to do is substitute m = 7 and n = 5 into the equation 4 + (m - n)^4. After substituting m and n into the equation, you will get: 4 + (7 - 5)^4. Use PEMDAS (parentheses, exponents, multiplication, division, addition, and subtraction). Parentheses is first, so solve everything inside of the parentheses first. 7 - 5 = 2. Now you have 4 + (2)^4. Next is exponents in pemdas, so solve the exponents. 2^4 = 2 x 2 x 2 x 2, or 4 x 4, or 16. Now you have 4 + 16. The last thing you have to do is add 4 + 16, which is 20. The answer is 20.