3)A dental researcher timed seven people, in seconds, in how long they brushed their teeth in the morning and afternoon, without disclosing the times in between. Assume the distribution is normal. Is there any difference between the mean time spent brushing teeth in the morning and the afternoon? Use a 10% level of significance. AM 36 45 55 62 48 42 39 PM 32 41 50 62 40 45 39