Answer :

400, because 2*2 is 4 now add your two 0s and you get 400 hope that wasnt confusing to much 
It is 400. You multiply the first numbers and then add the remaining zeros. For example. 500x500 would be 5x5=25 including the 4 zeros in the two 500's making 500x500=250000. Hope that makes sense.

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