Iq scores are measured with a test designed so that the mean is 116116 and the standard deviation is 1818. consider the group of iq scores that are unusual. what are the z scores that separate the unusual iq scores from those that are usual? what are the iq scores that separate the unusual iq scores from those that are usual? (consider a value to be unusual if its z score is less than minus−2 or greater than 2.) what are the z scores that separate the unusual iq scores from those that are usual? the lower z score boundary is nothing.