Facebook, Inc. reported the following figures for the year ending December 31, 2023:

4. 
   
   • Net Sales: $134.7 billion
   • Cost of Goods Sold (COGS): $23.4 billion
   • Operating Expenses: $65.8 billion Calculate: a) Gross profit margin. b) Operating profit margin. c) Net profit margin if the net income for the year is $44.3 billion.