Complete the following items. For multiple choice items, write the letter of the correct response on your paper. For all other items, show or explain your work.Consider the expression (r³m / r^⁻m t⁴ⁿ)¹/ⁿ . (r¹/ⁿ / t²/m )^⁻m .

c. For what values of r will the expression you found in part (b) be a real number? Explain your answer.