by Diana Filer 

1.  Herd immunity happens when a large part of a community, for one reason or another, becomes immune to an infectious disease.  With the corona virus, 50-67% of an area’s    population would need to be resistant before herd immunity starts working.
2.  A bitcoin is currently worth about $6,500 US.
3.  Harriet Brooks (1876-1933) was Canada’s first woman nuclear scientist.  She studied at McGill University under Sir Ernest Rutherford, ‘the father of nuclear physics’, during his 9 years as a professor there.  She is best known for her work on radioactivity.
4.  Joseph-Armand Bombardier, 1907-1964, invented the Snowmobile.
5.  There are 54 fully recognized countries in Africa.  Two other states are disputed territory:- Western Sahara and Somaliland.