1. It is the generation of photoelectrons.
2. The existence of a threshold frequency.
Viscosity, is a state of matter where it resists flow or may be in thick semifluid form because of friction acting inside the matter.In this case, hot oil room temperature would lessen the viscosity of the oil (animal oil). Thank you for your question. Please don't hesitate to ask in Brainly your queries.
This piece of porcelain is called a streak plate. This method is a method of rapid qualitative isolation and was developed by Robert Koch. It was developed to obtain pure bacterial cultures.
