Final answer:
The astronomer would position her telescope to an altitude of Below 90 degrees to observe the star Pollux. This is due to the astronomical positions of celestial poles relative to an observer's latitude on Earth.
Therefore, the correct answer is: a) Above 90 degrees
Step-by-step explanation:
To see the star Pollux, an astronomer positions her telescope to an altitude of Below 90 degrees. This is because the celestial poles are positioned in the sky according to the observer's latitude. For an observer at 38° N latitude, the north celestial pole appears above the horizon at an altitude equal to the observer's latitude, meaning Pollux, which is not a circumpolar star, will follow a path across the sky that is partly below the horizon and never exceeding the observer's zenith.
The altitude of a star's position is always measured as an angle up from the closest point on the horizon towards the zenith, which is directly overhead. Since Pollux is not at the zenith or above it, it cannot have an altitude above 90 degrees.
The altitude of a celestial object, such as a star, is its angle above the horizon when observed from a specific location on Earth. The altitude is measured in degrees and ranges from 0 degrees at the horizon to 90 degrees directly overhead (the zenith).
If an astronomer wants to observe the star Pollux, she would position her telescope to an altitude above the horizon.
It's worth noting that altitudes are measured from 0 to 90 degrees, and anything above 90 degrees is not a valid measurement in this context.