Answer:
a. 26%
b. 28.2%
Step-by-step explanation:
Consider the following formula:
Gross profit ratio = Net sales - Cost of sales / Net sales
Walgreen's 2015 gross profit ratio: (103444-76520)/103444
26.0%
Walgreen's 2014 gross profit ratio: (76392-54823)/76392
28.2%