List two advantages and two disadvantages to worldwide use of si.

Two disadvantages Retooling and conversion of machines and equipment in the US would be very expensive

Some expressions in the English language would eventually be quite strange: “A miss is as good as a mile”; “Inching along…”; “Ten gallon hat”; “The whole nine yards” & etc. Advantages everything is based on 10 so its easy to switch units

scientists can share info internationally

the body's situation won't change the forces are equal opposit and on the same body

c) up is the direction the magnetic force is acting on the charge.