Based on all tax returns filed in 2001, the Internal Revenue Service found the total deduction claimed on an itemized return by someone with an adjusted gross income between $30,000-$50,000 per year to be normally distributed with standard deviation $770. Suppose 20 IRS agents each randomly selects 10 returns and calculates the standard deviation of his/her sample. Approximately how many agents will calculate a standard deviation? $1000? Approximately 19 of the agents will calculate a standard deviation greater than or equal to what amount?