7. A plane is in a holding pattern about an airport. The function d (t) = 70 sin (0.65 t) + 150 represents the distance d, in miles, that the airplane is from the airport at time t in minutes. At what times is the plane 100 miles from the airport? (round your answer to 2 decimal places) 8. The leaning tower of Pisa is 184.5 ft. tall. A tourist standing 123 ft from the base, measures the angle of elevation to the top of the tower and finds it to be 60. How far from vertical (90) is the tower leaning? 9. Show that if tan A = x + 1 and tan B = x - 1 then 2 cot(A - B) = x 10. A triangular lot has one side of 1.8 m, a second side of 7.5 m and the third side is 9 m. Find the area of this lot. 11. Using trigonometric form divide 3-3i 1-31 then give the answer in rectangular form. 12. Verify the identity: cosx cot x + sin = cscx