An ice cream stand offers cake cones, waffle cones, or cups to hold ice cream. you can get vanilla, chocolate, strawberry, pistachio, or coffee flavored ice cream. how many outcomes are possible?

You can have 15 possible outcomes because if you take all the ways to hold the ice cream then have every flavor the that all adds up to 15 like this                                          Cake    Waffle  or Cup                                                                                         1 vanilla  2 vanilla    3 vanilla                                                                          4 chocolate  5 chocolate 6 chocolate                                                                    7 strawberry etc. 

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.