Were there under 150,000 American troops in Vietnam in 1965?
In 1965 the president announced an intention to increase the amount of troops to 125,000. There were only 75,000 prior to 1965.
The answer is yes.

Are both founders of Ben & Jerry's still involved in the company?
Ben & Jerry's was founded by Ben Cohen and Jerry Greenfield. The founders sold the company to Unilever in 2000.
The answer is no.

In isopropyl alcohol, is the solubility of salt low?
Isopropyl alcohol is unique in the sense that salt remains visible. When salt has high solubility, it becomes invisible.
The answer is yes.

Is material from an aloe plant sometimes enclosed in petroleum-derived products?
Aloe vera gel is sometimes kept in plastic packaging. Plastic packaging is derived from petroleum.
The answer is yes.