For normally distributed data, approximately what percent of scores will fall between -1 to +3 standard deviations (the mean)?

- - - - - - -- ----- - - - - - - - -. M-30 M-20 M-O Mto M+20 1+ 30 For normally distributed data, approximately what percent of scores will fall between -1 to +3 standard deviations (the mean)? O 64% O 34% O 70% O 84%