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In what follows I'm going to call the design above the "unit shape" and imagine it repeated endlessly along a line - rather like a stream of paper coming off a roll.
Try to design a new unit shape (probably simpler than mine) to make a strip which looks the same after a 180 $^\circ$ rotation.
In other words, make it so that you could not say whether the torn off strip had or had not been rotated.
First the original strip could have a mirror across it.
This illustration shows the right side as the reflection of the left side
Can you create a unit shape so that the strip has reflection symmetry across a vertical mirror line ?
And where would the mirror line need to be to be placed ?
Consider a watch face which has identical hands and identical marks for the hours. It is opposite to a mirror. When is the time as read direct and in the mirror exactly the same between 6 and 7?
Using the 8 dominoes make a square where each of the columns and rows adds up to 8
The ten arcs forming the edges of the "holly leaf" are all arcs of circles of radius 1 cm. Find the length of the perimeter of the holly leaf and the area of its surface.