Which of the following represents a system that is completely open? a capped soda bottle a pressurized canister of helium gas a pressure cooker a pot of boiling water

True or false, the three major scales used to measure earthquakes are mercalli scale, richter scale and magnitude scale

Asample of silver (with work function ? = 4.52 ev) is exposed to an ultraviolet light source (? = 200 nm), which results in the ejection of photoelectrons. what changes will be observed if: silver is replaced with copper (? = 5.10 ev) more photoelectrons ejected no photoelectrons are emitted fewer photoelectrons ejected more energetic photoelectrons (on average) less energetic photoelectrons (on average)

Structure of the atoms: discovery of the nucleus in 1909i need answering all of these questions