My homework does not accept 2.000 as the correct answer, but that is what everyone on this website says the answer is;

Rachel loves to bake cookles, but she has an old oven that has trouble maintaining a constant temperature. If the acceptable temperature range for making the cookles is 350 plus or minus 6 degrees, what is the allowable standard deviation in the temperature of her oven in order to achleve a SIx Sigma level of quality? (Round your answer to 3 decimal places.) ( Answer is complete but not entirely correct