Why do computers have both main memory and secondary storage?

Our primary purpouse as electricians is to do wich of the following core concepts? a: install electrical components in a way they can be upgraded b: install electrical equiptment in a way that reduces heat c: install electrical systems in a safe manner d: only b and c

Visualizing a game of “tag” to remember the meaning of contagious

Verify each identity[tex] \frac{csc}{cot \: x \: + \: tan \: x} = cos \: x[/tex]