A computer manufacturer sells keyboards tona retail outlet, each at a cost of $4 more than the manufacturing cost. The retail store then sells each keyboard to the public, charging 20% more than they paid to the manufacturer. If m represents the manufacturing cost (in dollars), find a function A(m) for the price of buying a keyboard at the retail store

Sam is a waiter at a local restaurant where he earns wages of $5 per hour sam figures that he also eams about $3 in tips for each person he serves sam works 6 hours on a particular day. if n represents the number of people sam serves that day, which of the following functions could sam use to figure ehis total earings for the do o a. en) = 30 o b. en) = 5n+ 18