Two surveyors measure the distance across a river that they cannot cross. They drive two stakes into the ground and find that the distance between the stakes, the baseline, is 15 meters. They choose a pole as a landmark on the opposite side of the river. This forms a triangle, with the two stakes as two corners and the pole as the third corner. When sighting the pole from the two ends of the baseline, the two angles formed on their side of the river are 82 and 67. The distance from the baseline to the pole calculated using the triangulation method is approximately _____.
A) 76 meters
B) 83 meters
C) 26 meters
D) 43 meters
Question 2According to the inverse square relation, _____.
A) the square of the magnitude of a light source is inversely proportional to the square of its wavelength
B) the mass of a star is inversely proportional to the square of its distance from Earth
C) the flux you receive from a light source is inversely proportional to the square of the distance to the source
D) the temperature of a star is inversely proportional to the square of its visual wavelength when viewed from the source
Question 3In the context of light curves, observations of an eclipsing binary system can directly tell astronomers not only the masses of its stars but also their _____.
A) orbital periods
B) diameters
C) intensity of magnetic fields
D) temperatures
Question 4Cool stars emit a great deal of ultraviolet radiation that you can't see, and hot stars emit plenty of infrared radiation.
Indicate whether the statement is true or false
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