What discoveries or further ideas were most critical for Copernicus' hypothesis that the planets orbit the sun to be promoted to a theory?

Ammonia enters the expansion valve of a refrigeration system at a pressure of 10 bar and a temperature of 18oc and exits at 6.0 bar. the refrigerant undergoes a throttling process. determine the temperature, in oc, and the quality of the refrigerant at the exit of the expansion valve.

Why is it important always to use horizontal bars in unit fractions when performing unit conversions?

The mantle is made up of which structural zones?