What is the length of the following lines?
is it even so? then i defy you, stars!
thou know'st my lodging: get me ink and paper,
and hire post-horses; i will hence to-night.
hexameter
pentameter
decameter

Given that the line length is measured by the same system the poetic ‘’foot’’ is, we have to check the placement of accented and unaccented syllables during, in this case, just a poetry line. Now, since this piece of theoretical information, we can determinate, certainly, that these three poetic lines given are pentameter long. In order to verify it empirically, recite the poem and you will find out the five accented syllables just fit properly.  

That’s nice! sounds really fun.