A period in 24-point font (.) is about 1mm in diameter. SARS-CoV-2 has a diameter of 80 nm. The prefix “milli” means 1000, which tells you there are 1000 millimeters (mm) in a meter. The prefix “nano” means 109 (1 billion), which tells you there are 1 billion nanometers (nm) in a meter. Approximately how many SARS-CoV-2 viruses could fit in that period? (Hint: There are 106 nm in 1mm).

A total of 12,500 SARS-CoV-2 viruses

Explanation:

Consider a trillion against a thousand, there exists a difference of a million, which means a nanometer will be a million times smaller as compared to one millimeter:

see below for a milli  divided by nano

1/1000  ÷  1/1000,000,000  =  1000,000,000  ÷ 1000 =  1000,000

(in reference to the hint given in the question statement)

The question puts one millimeter against 80 nanometers. The calculation for this will be given as follows:

1/1000  ÷  80/1000,000,000 =    1000,000,000 ÷ 80,000  =  12,500  

According to the above working, there are 12,500 SARS-Cov-2 viruses thatg can fit into one period.

he is very short, and he can only reach halfway up on the elevator buttons. but on a rainy day, he has his umbrella with him, and he uses it to poke the button at the top.