(A) The word ‘whereby’ can be used instead of
– ‘by means of” or
– ‘through which’
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Click here for the standard & non-standard usage of the word : http://dictionary.cambridge.org/dictionary/british/whereby
(B) The word ‘where’ can be used as a conjunction in the following ways :
– in or at what place, part, point, etc.:
Find where he is. Find where the trouble is.
The book is where you left it.
Where ignorance is bliss, ’tis folly to be wise.
Use the ointment where pain is felt.
I will go where you go.
– in or at which place; and there:
They came to the town, where they lodged for the night.