0.04 plus root number 0.04= root number 0.2 times root number 0.2=0.2.

The root sign of 10 square, and the square and the root sign cancel each other equal to 10.

Dude, I don't think your basic knowledge is very hard. I recommend you to buy an all-pass book, which is very easy to use. I am using it now.

Anyway, good luck.