The act of replacing variables with numbers in an expression is called what

Is it true that product of 3 consecutive natural numbers is always divisible by 6? justifyyour answer

In a graph with several intervals o data how does a constant interval appear? what type of scenario produces a constant interval?

Arestaurant chef made 1 1/2 jars of pasta sauce. each serving of pasta requires 1/2 of a jar of sauce. how many servings of pasta will the chef be able to prepare using the sauce?