What is the answer? For the first is Tom's PPF a straight line or a curve?

Tom's lawn service specializes in mowing lawns and trimming bushes. Tom has 4 hours to devote to lawn services. In 1 hour, he can mow 2 lawns or trim 7 bushes. Tom's PPF is a straight line . Tom's PPF intersects the graph's axis for mowing lawns at and intersects the graph's axis for trimming bushes at I: . (Enter your responses as whole numbers.) Tom's opportunity cost of mowing lawns in terms of trimming bushes is El trimmed bushes per mowed lawn. (Enter your response rounded to two decimal places.)