You know the mean and the standard deviation so the key thing will be the shape of the distribution, so is it uniform or normal or ... If its uniform then the width is 4 degrees and the +/-1 std dev is ~2 degrees so its easy to calc. If its normal you should know the percentage of data that lies within +/-1 std dev of the mean. I presume the assumption is the shape of the distribution as its not indicated in the question.