Answer: 40 tons
Step-by-step explanation:
One Ton= 2,000 lbs.
80,000/2,000= 40
A construction crew wants to hoist a heavy
beam so that it is standing up straight. They
tie a rope to the beam, secure the base, and
pull the rope through a pulley to raise one
end of the beam from the ground. When
the beam makes an angle of 40 degrees with the
ground, the top of the beam is 8 ft above
the ground.
Th e construction site has some telephone
wires crossing it. Th e workers are
concerned that the beam may hit the wires.
When the beam makes an angle of 60 degrees with
the ground, the wires are 2 ft above the top
of the beam. Will the beam clear the wires
on its way to standing up straight?
<span>Math - Steve Thursday, April 16, 2015 at 6:22pmwe see that the length of the beam is
8/sin40 = 12.45 ft
At 60 degrees, the top is
12.45sin60 = 10.78 ft high
So, the wire is 12.78 ft up.
Since the beam is only 12.45 ft long, it will not touch the wires.</span>
<h3>
Answer: Choice B) 468 cm^2</h3>
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Explanation:
As the diagram shows, we have a triangular face with a base of b = 18 and height of h = 13. The area of this triangular face is:
A = 0.5*b*h
A = 0.5*18*13
A = 117 square cm or cm^2
This represents the area of one face, but there are 4 identical copies of this triangular face assuming this tetrahedron is a regular polyhedron. So we have a total surface area of 4*117 = 468 cm^2 which points us to choice B
This is the amount of paint you'll need to cover the outer surface of the pyramid, or you can think of it as the amount of wrapping paper needed. This assumes there are no gaps or overlaps.
Answer:B
y=13cos(1/13x)+13
Step-by-step explanation: