Laura Lopez sells gifts certificates for $72 each. She purchases each gift certificate for $14 and spends $4,500 for fixed costs. Do not enter dollar signs or commas in the input boxes. Round your answers to the nearest whole number. a) Calculate operating income if Laura sells 370 gift certificates Operating Profit: $Answer 16960 b) Calculate the revenues needed to obtain an operating income of $3,800. Required Revenue: $Answer 144 Incorrect