20. [0/5 Points] DETAILS PREVIOUS ANSWERS SCALCET7 7.2.038. Evaluate the integral. (Use C for the constant of integration.) /csc 4 ( x ) cot 6 ( * ) dx 3 7 9 3 tan N/X NO/X tan 3 tan tan 3 3 + + + C 3 256 192 3584 4608 3584 tan 192 tan NO/X 256 tan NIX X5. [5/7 Points] DETAILS PREVIOUS ANSWERS SCALCET8 6.4.034. MY NOTES PRACTICE ANOTHER The Great Pyramid of King Khufu was built of limestone in Egypt over a 20-year time period from 2580 BC to 2560 BC. Its base is a square with side length 756 ft and its height when built was 481 ft. (It was the tallest manmade structure in the world for more than 3800 years.) The density of the limestone is about 150 lb/fts (a) Estimate the total work done in building the pyramid. (Round your answer to three decimal places.) 1.653 x 1012 ft-lb (b) If each laborer worked 8 hours a day for 20 years, for 330 days a year, and did 240 ft-Ib/h of work in lifting the limestone blocks into place, about how many laborers were needed to construct the pyramid? 89285.7 * laborers Need Help? Read It