Abread recipe calls for 1/3 cups of butter you want to make 1/2 off a batch. how much butter will u need

A full recipe requires 1/3 cups of butter.
Since you want to make half the batch, then you will use half the amount of butter.

you will need (1/2)(1/3) = 1/6 cups of butter

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.