Question

A theodolite is set up over point A. The vertical distance from point A to the center of the theodolite is 4.66 feet. Point B which is 900.00 feet (slope distance) away from the center of the theodolite is observed at a zenith angle of 84°4530". What is the elevation of B to the nearest 0.01 feet if the elevation of A is 1000.00 ft. 7. If a Philadelphia rod is held vertically on B in problem 7 and the center of the crosshairs falls on the 5.91 foot mark, what is the elevation of B? (Use the same zenith angle and assume the distance from the theodolite center to the 5.91 foot mark is 600.00 feet.) 8. In underground surveying, station points are commonly located on the roof (or back) of the tunnel. If the cross hair intersects a point 4.56 feet below the backsight at A and 7.22 feet below the foresight at B, what is the elevation of B if the elevation of A is 2356.66 feet? 9. 10. A level is set up on a planar slope. The backsight reading on point A is 1.56 feet at a horizontal distance of 200.00 feet. The foresight reading on point B at an equal distance is 12.67 feet, what is the grade of the slope in percent to the nearest 0.01%? Be sure to include the appropriate sign from backsight to foresight..

the andwers to the questions are:

7. 1086.88

8. 1053.56

9.2359.32

10. -2.78%

i know how to do number 7 but need help on 8,9 and 10

Answer 1

900 466 h: 82.22. 1000 eleva B1000 +466+82.22 o86.88 5.9 u'us 30 1-66 5481