That depends on what you mean. It could be possible for an element to possess itself, but this is not possible with some elements that refer to non-physical existences. There could be days in a day,...
I'm not sure I understand your question. but there are 3 days in between the seventh and fourth day you mentioned
10 Actually it would only be 7 with 3 days repeated.
That is just a general statement. There is no specific amount of days within "several days." This could be from 3 or 4 days to a year.
I assume you mean months which about 2 months are in 60 days. If not 60 days are in 60 days.