A multimode step-index fibre has a core index of 1.484 and a cladding index of 1.456. When the fibre is overfilled with light emitted from a light-emitting diode (LED), estimate the pulse broadening 87 (in ns/km) and the bandwidth-length product (in MHz-km) of the fibre. (2 marks) Repeat the calculation in (a), when the fibre is filled with light emitted from a laser diode over a cone limited to half of the maximum acceptance angle of the fibre. Compare the results with those obtained in (a) and discuss. (6 marks)