Suppose a cup of cocoa cooled from 90 c to 60 c after 10 minute in a room whose temperature was 20 C A) what is the temperature after 15 minutes?
B) How long will it take to decrease to 45 C

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