2 question about Google

Hi everyone,

last day's im thinking, how google can catch cloaking text on website. For example by css cloaking - text have the same color as background

Second question, i read somewhere, google know so website had bad content by bouncerate. But, if I will not use any google service (analytics, webmaster tools) how he know bounce rate of my website?

Eng is my sencond language, I'm sorry for my bad grammar and thanks everyone who can help me

1) It will detect that the text color is not readable on given background. This is maybe the simplest thing to detect, you may try with some advanced techniques (e.g. javascript or cloaking by IP). Best cloakers out there combine several ways, some of which are private. I heard it could helpful to use time-based cloaking because the bot loads the page faster than a normal user, but, to be honest, I don't know for sure as am not much into the cloaking thing.
2) It is done through Google Toolbar.