I have no idea about the question...
A 64 bit ram can just save the pattern of one column, how can it be read again to fill in the second columns and so on...
Please click the attachment below to enlarge the photo.
Maybe he is asking how you would use 8 * 8 bit bytes to make up 64 bits for each row of data?
Perhaps you would know from the lectures you have been having if this is the case or not.