List the factors that affecting frictional force ?​

The transfer of heat through the movement of a gas or liquid a. convection b. conduction c. radiation

Where is the potential energy throughout the loading, cocking, and releasing of the trebuchet?

Iron is a transition metal with multiple oxidation numbers. (answer the following) a. what is the iron (ii) ion? how does it differ from the iron (iii) ion? b. if iron were to bond with oxygen, predict the formula for each oxidation number of iron. c. how would each formula be named?