Clorox bleach can be safely used to purify water in the event of an emergency. Clorox recommends adding 2 drops of bleach to 1 quart of water or 8 drops of bleach to 1 gallon of water. Clorox warns that only regular bleach is suitable for purifying water; scented bleaches are not safe for water purification.
The pass mark for the Theory Test is 86%, so you'll need to answer 43/50 multiple choice questions correctly to pass. And for the hazard perception section of the test, you need to score 44/75. You must score a pass in both sections of the theory test to pass the overall test. What is the current pass rate for the theory test? The 2015/16 pass rate for the theory test is 49.3%*, which means just over half of all people who sit their Theory Test fail it.
To pass you need to correctly answer 43 out of the 50 questions (i.e. 86%). The examination process Before you start the actual test a short video tutorial will explain how the test should be undertaken.