Answer all the questions below and press submit to see how many you got right.
Centimeter : A centimeter ($cm$) is $\frac{1}{100}$ of a meter.
Circle : A circle is a two-dimensional shape. The boundary of a circle is a set of points that has the same distance (the radius) from the center of the circle.
Circumference : The perimeter of a circle is called circumference. The length of the circumference $C$ can be calculated as $C=2\pi r=\pi d,$ where $r$ is the radius and $d$ the diameter of the circle. This means that the circumference of a circle with diameter 1 $cm$ (radius 0.5 $cm$) is about 3.14 $cm.$
Diameter : The diameter of a circle is the length of a line segment from the boundary of a circle through the center of the circle to the boundary on the other side of the circle.
Pi : Pi or $\pi$ is an irrational number approximately equal to 3.14 that is defined as the quotient of the circumference and the diameter of a circle.
Radius : In a circle or sphere the radius is the distance between the center and the boundary.
What is the circumference of a circle with radius 2 cm? Approximate $\pi$ by 3 in the calculation.
Leg of a right triangle : A leg of a right triangle is one of the two sides in a right triangle that form the right angle.
Line : A line AB is a one-dimensional shape that includes the points A and B, all the points on the line segment in between A and B and all the points of the straight extension of the line segment beyond A and B. A line does not have an endpoint.
Reflection : A reflection is a transformation that mirrors a shape at a line. Reflections turn shapes into congruent shapes.
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.
Triangle : A triangle is a polygon with three corners and three sides. You can calculate the area of a triangle by multiplying half the length of the base by the height on that base. The sum of the interior angles in a triangle is always $180^{\circ}.$
Vertical : In the direction from down to up.
Which of the figures do you get if you reflect the right triangle in the upper part of the picture on a vertical line?
Area : The amount of unit squares that is needed to cover a 2-dimensional shape.
Cube : A cube is a three-dimensional shape with 6 faces that are all squares. A cube has 8 corners and 12 edges.
Edge : An edge of a shape is a line segment between two corners of that shape.
Length : Length is the attribute of a one-dimensional shape that can be measured with a measuring tape.
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 $m^2.$
Surface area : The surface area of a three-dimensional shape is the area of the surface of the three-dimensional shape. For example the surface area of a cube with edge length 1 $cm$ is 6 $cm^2.$
What is the surface area in $cm^2$ of a cube with edge length 8 cm?