Generally speaking Saliva tests are less accurate than urine tests and yes...Im not quite sure why you would be concerned if you can pass a urine test. Alcohol stays in your mouth until it evaporates...
No,
saliva drug tests prime detection range for THC ( cannabis) is normally up to 48 h. Urine - 2-7 days (single use) , up to 10-12 weeks (prolonged use).
best way is index cards writing stuff down always helps for studding habitsanother way is acronyms using acronyms help break down stuffalso you can play games with it make it like a TV show game...