Cube : A cube is a three-dimensional shape with 6 faces that are all squares. A cube has 8 corners and 12 edges.

Number : A number $x$ is a mathematical symbol representing a quantity.

Liter : A liter is a unit for measuring volume. A liter is the volume equal to the volume of a cube with side length 10 cm. 1 liter equals $1,000 cm^3.$

Milliliter : A milliliter is a unit for measuring volume equal to $\frac{1}{1000}$ of a liter.

Thousand : Thousand refers to the number $1,000=10^3.$

Thousandth : A thousandth refers to the number $\frac{1}{1,000}=0.001=10^{-3}.$

Area : The amount of unit squares that is needed to cover a 2-dimensional shape.

Centimeter : A centimeter ($cm$) is $\frac{1}{100}$ of a meter.

Half : A Half is the number equal to $\frac{1}{2}=0.5.$

Length : Length is the attribute of a one-dimensional shape that can be measured with a measuring tape.

Product : A product is the result of a multiplication.

Right angle : A right angle is an angle equal to $90^{\circ}.$

Right triangle : A right triangle is a triangle that has a right angle. The sides that form the right angle are called legs, the third side is called hypotenuse. The area of a right triangle is half the product of the lengths of the two legs. The Pythagorean theorem is an important theorem for right triangles that allows to calculate the third side of a right triangle given the other two.

Square centimeter : Square centimeter or $cm^2$ is a unit of measurement for measuring area. 1 square centimeter is the area of a square with side length 1 $cm,$ so 10,000 $cm^2$ are one $m^2.$