To calculate for the energy
content of food you will just continue from the last help page in the previous
question. The last page left off with the calculation of energy in joule or
calories for the walnut, and you divided by a 1000 cal/kcal or 1000 J/kJ to
convert your number into kilo. Remember this is what the units on the back of
the package really are in.

The last thing is to
compensate for the entire mass of a package. If you calculated the energy of
one walnut which weighs only a gram or two than what would the energy be in the
entire bag or one serving size? I think you get the drift and can come up with
some way of calculating it. Check to see
if it make sense from what you know about calories.