a solution is prepared by dissolving 23.7 g of cacl2 in 375 g of water. the density of the resulting solution is 1.05 g/ml. the concentration of cacl2 is % by mass.

This statement is true.

Answill have their license immediately suspended for six(6) months;

It depends on the subject for me. some exams are easier than others so i usually go through it and answer questions i know based on my general knowledge, then double check after. going through the lesson can a lot  because the exams can be  very lesson-specific, but sometimes they are ridiculously long so a lot of people don't take the time. i did find that, when i went through the lessons, i was making 100's on my exams vs strictly using + the internet and  i make 90's.