One space between words. No space between the last word and the period or interrogative. Two spaces after the period or interrogative.
There were 3 blank spaces in mendeleev's Periodic Table. He left it for the elements which were not discovered at that time.
One.
Mendeleev left 3 blank spaces for the elements that had not yet been discovered.
If you double space (hit the return key twice), then type the inside address, there will be one blank line between the date and the inside address. One blank line is the appropriate space.
Unless otherwise indicated, as in a particular assignment, there should be two spaces between sentences in order to follow proper guidelines. Words should only be separated by one space.
It doesn't have any spaces between it.
A wheel with 64 spokes will have 64 spaces between the spokes.
I've counted 166,324 words / 767,308 words (no spaces) / 941,019 (with spaces) / 4,973 paragraphs / 13,460 lines.
None.
One.
One.
That would depend on which words you use (as they have different numbers of letters).