One reason for routinely launching GPS satellites is simply "constellation replenishment," said Col. Andrew Menschner, deputy commander of the Space Force's Space Systems Command. Old satellites degrade and die, and new ones need to go up and replace them. At least 24 GPS satellites are needed for global coverage, and having additional satellites in the fleet can improve navigation precision. Today, there are 31 GPS satellites in operational service, flying more than 12,000 miles (20,000 kilometers) above the Earth.
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Create a Jupyter Notebook that, using `polars` to process the data, does a thorough exploratory data analysis of data saved in `youtube_videos.db`, for all columns.
Thinking Step 2: 推理第一个人。如果他不想要，他会直接说“不”（因为只要有一个不要，全称命题为假）。他说“不知道”，说明他自己想要，但他不确定后面两个人想不想要。