making a spiral

Being self-taught, it might be obvious to others, but I can't find anything in the help files either.
I'm connecting an outer circle to an inner circle by a spiral. I'd like
to be able to control the # of revolutions from 3/4 to 2 revs the spiral takes before contacting the 2 circles.
I'm using 2000LT
thanks NetMax
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HiHo; The basic spiral is r=e?i where ? and i are Super scripts and theta is in radians. Plot the points and connect

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