A 40-foot T. V. antenna stands on top of a building. From a point on the ground, the angle of elevation to the top and to the bottom of the antenna measures 56° and 42° respectively. How tall is the building?

61.5

Step-by-step explanation:

In this case to calculate the height, we do the following:

The first is the graphic, attached image.

Then the calculations.

b / d = tan (42 °) = 0.9

d = b / 0.9

Then we have to:

(40 + b) / d = tan (56 °) = 1.48

(40 + b) = d * 1.48

Replacing we have:

(40 + b) = (b / 0.9) * 1.48

40 + b = 1.65 * b

1.65 * b - b = 40

b = 40 / 0.65

b = 61.5

Therefore the height is approximately 61.5

answer: expected value of x = 1.0

step-by-step explanation:

p(x=0) = 0.25

p(x=1) = 0.50

p(x=2) = 0.25

expected value for x = 0×0.25 + 1×0.5 + 2×0.25 = 1.0