Retaking Subject Tests

<p>Hi, I'm a rising junior and I took my first SAT II - the chemistry SAT II. I got a 740 which I was dissapointed by (740 is the highest score I would consider retaking). I was wondering if it would be worth it to retake it. I could restudy the material myself but I wouldn't be taking chemistry next year, so I am asking those of you who have retaken science SAT II's the next year...is it a possibility? or do you forget too much of the material?</p>