True or false given relation r1, where r1 contains n1 tuples and a is an attribute of r1, the minimum possible size in tuples of σa=5(r1)

B, it is easy to scan for key information. there are times when a lot of information is included in a business letter. the block letter format you find key bits of information quickly, without having to read through the whole paper.

Answer the car to the left must yield the right of way to the vehicle on the right;

It is called "choke.