How many?

Yards

The yard is an English unit of length, in both the British imperial and US customary systems of measurement, that comprises 3 feet or 36 inches. Did you know that a yard of ale, whilst being 2.5 imperial pints of beer, is so called because the glass is a yard long.

Nanometres

The nanometre (international spelling as used by the International Bureau of Weights and Measures; SI symbol: nm) or nanometer (American spelling) is a unit of length in the metric system, equal to one billionth (short scale) of a metre (0.000000001 m). To demonstrate just how small a nanometre is, it is commonly used to measure atoms and molecules. A typical virus is around 100 nanometres wide. The coronavirus, known as COVID 19 is believed to be between 60 to 120 nanometres wide.