Which of the following is written in correct scientific notation? -4x10²
2.1 x 100
39 x 10
-0.3x10

please help i have to turn this in in the morning

It will cost $540i think

First step is to get rid of the square root. remember that a square root is the same as raising to the (1/2) power. see below: multiply exponents per exponent rules to get: remember you subtract exponents from the denominator and add exponents in the numerator so: simplify further: so a is the correct choice. if you don't understand this google exponent rules and it will you understand. look at the image results.