3. Write the equation for the D exponent calculated while drilling a well. W hy is the d- exponent calculated? How should the d-exponent change as burial depth increases {draw a dexponent depth trend). Whatdoes that trend imply about the formations you are drilling as depth increases ? What might cause the slope of the d-exponent depth trend to increase? To decrease? (10 points] 4. Why do we calculate a sample lag time? You are drilling at 20,000 feet. The wellbore is g" in diameter. What is the volume of the open borehole ? You are drilling with a 5\" drill pipe. What is the volume of the annulus ? The drill pipe has a 4" inner diameter. What is the volume that is taken up by the drill string? W hat is the capacity of the pipe? W hat do you assume in order to make these calculations? Assume that your mud pump has a 9 inch stroke and a 6 inch liner. What is the pum p volume per stroke? How many strokes are required to go from the surface to the bottom of the wellbore? How many strokes are required to go from the hit back to the surface? if your pum p is working at a rate of 90 strokes per minute, how much time does it take mud from the pump to reach the bit, and from the bit to the surface? If you are drilling at 30 ftlhour, and the bit is at 20.000 ft.what depth are the cuttings from that are arriving at the surface? (15 points)