N a heat engine, if 500 J of heat enters the system, and the piston does 300 J of work. What is the final internal (thermal) energy of the system if the initial energy is 1,500 J?

Which interval for the graphed function contains the local maximum? [–3, –2] [–2, 0] [0, 2] [2, 4]

Haley buys 9 pounds of apples for $3. how many pounds of apples can she buy for $1?

Janie has $3. she earns $1.20 for each chore she does and can do fractions of chores. she wants to earn enough money to buy a cd for $13.50. write an inequality to determine the number of chores, c, janie could do to have enough money to buy the cd.