Pls help me or I’m gonna fail

Which addition property is being illustrated below? (type commutative or associative) (6 + 7) + 1 = 6 + (7 + 1)

The lengths of all sides of a triangle are integers when measured in decimeters. one of the sides has length of 1 dm and another of 3 dm. find the perimeter of the triangle.'

Create a graph for the demand for starfish using the following data table: quantity/price of starfish quantity (x axis) of starfish in dozens price (y axis) of starfish per dozen 0 8 2 6 3 5 5 2 7 1 9 0 is the relationship between the price of starfish and the quantity demanded inverse or direct? why? how many dozens of starfish are demanded at a price of five? calculate the slope of the line between the prices of 6 (quantity of 2) and 1 (quantity of 7) per dozen. describe the line when there is a direct relationship between price and quantity.