Astrophysics, simple parallax error

[dink87522]

Homework Statement

Experiment 15.2 (note this is from a book about 5 years old, and the book has no solutions!). I am simply unsure how to calculate between parallax with 1% error and parallax with 50% error etc. Please see the scan I done of the page: http://img210.imageshack.us/my.php?image=savevx9.jpghttp://img210.imageshack.us/my.php?image=savevx9.jpg

Homework Equations

d = 1/p

The Attempt at a Solution

I've tried p=1/d = 1/30 (for ground based) although how do I then account for '50%' error etc? With this book not having solutions (or even answers!) I am just getting further confused as I know these should be very simple calculations.

 

[dink87522]

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