How much energy do gamma-ray bursts produce?

The gamma-ray burst GRB031332 produces a flux of 8 * 10^(-10) Watts per square
meter on Earth, for a period of about 90 seconds.  A followup measurement shows
that the burst occurred about 3000 Megaparsecs away.

(a) What was the luminosity of this gamma-ray burst?  How much energy did the
explosion produce during the 90-second burst period?

(b) How does that luminosity compare to that of the entire Milky Way galaxy?
Remember that the Sun's luminosity is about 4 * 10^26 Watts.

(c) The energy released by a supernova explosion is about 10^44 Joules.
About how many times more energy was released by this gamma-ray burst?