how long will 1 hit stay?

how long will 1 hit stay in my system if i dont do enything to force it out of my system? my BMI is 22 if that helps weighing 138lb and 5'5'' i dont have alot of fat its mostly muscle

will drinking 2 gallons of water every 4 hours work it out of my system? or a gallon of cranberry juice? im just trying to get to be sure before i smoke eny weed at all and what about niacin?

sorry for posting questions like this im not used to going without smoking weed and i really want to toke haha

is one lick of herb worth wat u were just saying u would do after.,.,i mean if i had to drink 2gakl of aqua after a lick.,.,ect.,.,it would defeat the purpose.,.,but to each his own.,.,i say drink a six pack of red stripe/hienikan and chill,.,

i mean after im done being high im thinkin about cranberry juice and smoking a bowl, i was drug tested today and passed so i might not have another for a while thats y i wanna steal a toke