Bill and rose are working together to plant 100 trees. it would take bill 45 hours to plant 100 trees. it would take rose 40 hours to plant 100 trees. which equation could be used to find p, where p is the amount of time, in hours, it would take rose and bill to plant 100 trees if they work together?

a) p/45+p/40 =1

b) 45/p +40/p =1

c) p/45+p/40 =100

d)45/p +40/p =100