D ..................................................................................................................
Since the area is 120 ft^2, and we know the length of the room is 15 ft, we can calculate the width.
120/15 = 8
To find the perimeter, we use the following formula
2l + 2w = P
2 (15) + 2 (8) = 46 ft
46.2 dollars for the large necklaces and 14 dollars and seventy cents for the small necklaces therefore she will earn $60.9
The diameter of the plate is 12, and the formula for finding circumference is diameter times pie. so you multiply pie (or 3.14 if you aren't using a calculator) times 12 and it should give you 37.6991. rounded to the nearest tenth, that's 37.7, hope I helped!
