Upon descent, an airplane is 15,000 feet above the ground. The air traffic control tower is 250 feet tall. The angle of elevation from the top of the tower to the plane is 16 degrees. Find the ground distance from the airplane to the tower. Round to the nearest foot, and enter the number only.

First step is to get rid of the square root. remember that a square root is the same as raising to the (1/2) power. see below: multiply exponents per exponent rules to get: remember you subtract exponents from the denominator and add exponents in the numerator so: simplify further: so a is the correct choice. if you don't understand this google exponent rules and it will you understand. look at the image results.

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