Which of the following is a noble gas ?

Which best describes how johannes kepler developed his laws of planetary motion

Which statement is true about a catalyst? a: a catalyst decreases the rate of the reaction. b. a catalyst is consumed during a chemical reaction. c. a catalyst lowers the activation energy of a reaction. d. a catalyst increases the reactant concentration during a reaction.

How does kepler second law of planetary motion overthrow one of the basic beliefs of classical astronomy