a) First, we need to find the perimeter of the hallway to determine the total length of carpet needed. To do this, add all the sides together:
3 ft + 3 ft 9 in. + 8 ft 9 in. + 10 ft + 3 ft + 5 ft = 33 ft 6 in.
b) Now, to convert 33 ft 6 in. to feet, we can do the following calculation:
33 ft + (6 in. / 12) = 33.5 ft
So, Stefan will need 33.5 feet of carpet to lay in his hallway.