1.) From a point 55 m up the ground on a vertical antenna pole, three cables are stretched into anchors which are located at the vertices of an equilateral triangle 20 m on a side. Find the length of each cable if the foot of the pole is equidistant from the anchors.

2.) A flat roof has an inclination of 30 degrees to the floor of a building. The roof is 50 m long (being parallel to the floor) and 20 m wide. Find the area of the projection of the roof upon the floor of the building.

3.) What is the area of the projection on the plane of an equilateral triangle 10 cm on a side, if one side is parallel to the plane and the other sides form an angle of 30 degrees with the plane?

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Please help.. Thanks in advance!