3 × 4 = 12. The area of the triangular faces is 12 cm². Image caption, Next work out the areas of the rectangular faces. The area of a rectangle is length multiplied by width. 7 × 3 = 21 ...

Schematic representation of the use of DNA origami nanostructures (DONs) to treat acute kidney failure. The triangular, rectangular or tubular nanostructures are injected in mice to target the kidney ...