@karolyn Pierced ears were traditionally seen as damaging your body in Japan, and are still a minority there (though ear piercings have mostly lost their stigma). In fact earrings and piercings are two different things in the Japanese language, the former being clips and the like, and often...
Um, why not just use the ruler tool to mark a straight line, then Image > Rotate > Arbitrary > OK? This will rotate it perfectly.
Skew is if the page was photographed instead of scanned, and there is (usually keystone) deformation from not holding the phone perfectly flat.
@Kaarme (& anyone else complaining about a high schooler's insecurities)
He's not putting together a rabbit cage bought from the store, he's putting together bulk cage parts (meant for arbitrary sized cages like you would buy wood to build a treehouse) bought from the equivalent of a dollar...