just need help with the second two parts

48:09 Time Remaining

48:09 Time Remaining Instructions Problems 4-6 Suppose the average american typically get 6.8 hours of sleep per night and the distribution is normal. A researcher randomly selects 20 americans and measures how long they slept the night after Daylight Saving Time began this year. The mean amount of sleep for the sample was 6.1 h (s = 1.3 h). Return Submit 1 point Caculate the estimated standard error. 0.291 1 point Calculate the t-scorc for the sample mean, Type your ansv. er 1 point If the researcher conducted the t-test with a two-t test, alpha - .05, she would conclude that the amount of averagc sleep was significantly different from 6.8 hours. O True False