Solve the given applied problems involving variation.The intensity I of light varies inversely as the square of the distance D from the source. If the intensity of illumination on a screen 5 ft from a light is 
find the intensity on a screen 20 ft from the light.
A. 2 foot-candles
B. 0.11 foot-candle
C. 0.13 foot-candle
D. 8 foot-candles
Answer: C
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Solve the problem.At lift-off, a rocket weighs 40.3 tons, including the weight of fuel. It is fired vertically, and the fuel is consumed at the rate of 2.16 tons per 1,000 ft of ascent. How much work is done in lifting the rocket to an altitude of 10,000 ft?
A. 5.11 x 105 ft?ton B. 2.95 x 105 ft?ton C. 3.31 x 105 ft?ton D. 3.49 x 105 ft?ton
The point P(x, y) on the unit circle that corresponds to a real number t is given. Find the values of the indicated trigonometric function at t.
?Find csc t.
A. - 
B. 
C. 
D. - 
Name the highlighted angle using the three-letter form of identification.
A. ?INE or ?ENI B. ?N C. ?CNL or ?LNC D. ?CNI or ?INC
Solve.The base of a triangle is 4 more than twice its height. If the area of the triangle is 78 square centimeters, find its base and height. 
A. height: -1 + 
cm
base: 2 + 
cm
B. height: 2 + 
cm
base: -1 + 
cm
C. height: -1 + 
cm
base: 2 + 2
cm
D. height: 2 + 2
cm
base: -1 + 
cm