Emma has twelve 2 1/2 inch building blocks. if they were stacked one on top of another, how tall would the stack be ?

30 inches

Step-by-step explanation:

you multiply the 2 1/2 cubes by the amount(12) which gets you 30 inches or 2 1/2 feet

30-inches

Step-By-Step-Explanation

2 1/2 * 12= 30

Unit cost is cost of 1 unit of a product, here its cost of 1 pound of sugar.
In first case unit cost is $1.10.
In second case cost of 2 pound = $1.98, or cost of 1 pound = [1.98/2] = $0.99.
In third case cost 3 pound = $2.85, or cost of 1 pound = [2.85/3] = $0.95.
We can see that as the quantity is increasing unit cost is decreasing.