Leeches are famous as blood-suckers. The species that feed on blood have special chemicals in their saliva that prevents blood-clotting. Many blood-feeding leeches attack only fish, a few attack any vertebrate (including people), and a few are specialists on another group of animals, like turtles or waterbirds. There are also lots of leech species that don't suck blood. They are predators, eating worms, snails, aquatic insects, and other invertebrates.
The Minimum: 2 Months or 100 Total Hours. Studying for the LSAT should really take at least two months (or about 100 total hours of studying). Any less than that, and you probably wonât get the practice youâll need to get through the concepts tested.
It all depends how much time you spend studying. Since you have a basic understanding, it should not take you a very long time to get your CCNA. Study the materials, understand the technology, and get some simulations exam i.e. Boson and go for it.) How long it will take you to pass the CCNA depends on your experience, and sometimes the test can still be tricky. I've passed most of the exams and can tell you that even to this day exam questions are difficult to understand even after preparing by going through what's considered a good Cisco study guide.