A population of 1,000 students spends an average of $11.40 a day on dinner. The standard deviation of the expenditure is $4. A simple random sample of 64 students is taken. (a) What is the expected value (in dollars) of the sampling distribution of the sample mean? $ What is the standard deviation (in dollars) of the sampling distribution of the sample mean? (Round your answer to four decimal places.) $ What is the shape of the sampling distribution of the sample mean? skewed to the right exponential normal skewed to the left uniform (b) What is the probability that these 64 students will spend a combined total of more than $776.31 ? (Round your answer to four decimal places.) (c) What is the probability that these 64 students will spend a combined total between $763.87 and $791.03 ? (Round your answer to four decimal places.).