Tree diagram (exercise #1)
  1. The largest living organism in the world today is a tree in Sequoia National Park named the "General Sherman."  To determine this tree's height, park rangers marked off a distance of 185 ft from (the center of) its base and then measured the angle of elevation to the top of the tree to be 56°04'.  Approximately how tall was the General Sherman if measured in:
     
    a.  feet b.  meters

    Building diagram (exercise #2)
     
  2. An office building casts a shadow of 50 m when the sun's angle of elevation is found to be 60.4°.  Determine the approximate height h of the office building when it is measured in:
    a. meters 
    b. feet 
     

  3. A painter leans his 24 ft ladder against a wall where the angle made with the level ground is 70°.  For each of the following, round the answer to the nearest whole number of feet and inches
    1. How far up the wall does the top of the ladder reach? 
    2. How far is the bottom of the ladder from the wall? 

    Antenna Tower photo (exercise #4)
  4. A 200 meter high antenna needs to be secured to the ground with a series of guy wires.  The angle formed with the (level) ground is designated to be 60°.  How long does each guy wire need to be?  Round the answer to the nearest foot.
     

  5.  
    A ground radar indicates that a Federal Express cargo plane is approaching from a line-of-sight distance of 2.5 miles.  If the plane's angle of elevation is 15°40', at what altitude is the airplane flying?  Round the answer to the nearest hundred feet.
    One Shell Plaza diagram (exercise #6)
  6. A television tower stands on the top of the One Shell Plaza building in Houston, Texas.  From a point 3000 ft from the base of the building, the angle of elevation to the top of the tv tower is θ = 18°26". If the building is 714 ft tall, how tall is the tower (to the nearest foot)?
     
  7. Find the Area for each of the following triangles. 
    a. Triangle diagram (exercise #7a)   b. Triangle diagram (exercise #7b)

     
  8. A forest ranger atop a 100 m observation deck watches a wild fire progress toward his position. 
    1. He measures the angle of depression to the leading edge of the fire to be 5°6'.  How far is the fire from the ranger's position?
    2. Two and one-quarter minutes later, he measures the angle of depression again, finding it has changed to 5°54'.  How far is the fire from the ranger's position at this time?
    3. What is the speed, in km/hr, at which the fire is moving toward the ranger?
    4. If the fire continues to advance at the same speed, then how many minutes after the second sighting before the fire reaches the ranger's observation deck?

     
  9. An overzealous trigonometry student, stands near the edge of a bridge overlooking a highway which passes underneath 30 feet below his line-of-sight.  He times an oncoming car as it passes a point in front of him where the angle of depression is 10° until it is directly beneath his position on the bridge.  If the car travels the distance between these two points in 2 sec, then find whether or not the car is exceeding the posted 55 mph speed limit.
     
  10. The distances between many astronomical bodies are so extremely vast that scientists typically use units of measure known as an Astronomical Unit (A.U.) or a light-year (ly).  In addition to these two units, another unit is the parsec (pc).  One pc is defined as the distance at which 1 A.U. of arc length subtends an angle of 1".  If an A.U. is 150,000,000 km, determine the number of light-years (rounded to the nearest hundredth) in one parsec.

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