SAT II U.S. History in 48~ days??

<p>Hey all,
So i am still on the fence about taking the USH SAT II test this upcoming June. i'm already taking Math IIC and Physics (Which i feel like i am going to fail). The thing is, i haven't been hitting the books hard for history which i really regret.
Anyways, June is coming up pretty soon so i am wondering if i have a chance to get 700+ in such a short amount of time. I heard that a test-taking variety would be nice for colleges.
I'm hoping to get 800 Math and 700+ in both physics and USH.
Also, could you post the most helpful books? I made the mistake of getting Barron's for USH... :( I also heard the essential content was good but i want to make sure.</p>