Definition: The associative property states that you can add or multiply regardless of how the numbers are grouped. By 'grouped' we mean 'how you use parenthesis'. In other words, if you are adding or multiplying it does not matter where you put the parenthesis.
Full Definition of ROSIN. : a translucent amber-colored to almost black brittle friable resin that is obtained from the oleoresin or deadwood of pine trees or from tall oil and used especially in making varnish.
Re: Whats in a rosin bag? There is a difference between a rosin bag and one of those hand drier bags. I believe rosin is made from pine sap or pine tar or something of the like, and it produces a tacky effect on the skin, enhancing grip. Those hand drier bags are just kitty litter or the equivalent, and they absorb moisture.