a survey, 29 people were asked how much they spent on their child's last birthday gift. the results were roughly bell-shaped with a mean of $35.9 and standard deviation of $9.5. estimate how much a typical parent would spend on their child's birthday gift (use a 98% confidence level). give your answers to 3 decimal places. express your answer in the format of ¯ x ± e. $ ± $