So how do we make access to space rapid, abundant, high-volume, and low-cost? Long-term stable investment in a method we can develop with technologies we currently have. No miracle drives or materials required. Just willpower and cooperation.
Scientists crack mystery of ancient Roman concrete's 2,000-year life span - The Washington Post
Ask Tom Why: What is the highest recorded height for a cumulonimbus cloud? - tribunedigital-chica
Jet stream - Wikipedia
32k - 52k ft
Flight altitude record - Wikipedia