What are the characteristics of prokaryotes? 1. a prokaryote lacks a well-defined nucleus. 2. a prokaryote cannot perform basic life functions. 3. a prokaryote lacks cell organelles. 4. a prokaryote is larger than a eukaryote. there can be multiple answers

Which of the following statements is true? a. most heat energy is easily recovered and used for useful actions. b. friction causes molecules to vibrate more slowly. burning air and gasoline in an c. engine changes chemical energy into mechanical energy. it is impossible to d. change mechanical energy into mechanical energy.