II. 19. This rule can be used for all integers, both positive and negative. 27. Impedance in an ac circuit plays the same role that resistance does in a dc circuit. 28. Two parallel wires a distance of apart carry the current i
Ellipsis I In compound sentences 电压的单位是伏特,电流的是安培。 Voltage is measured in volts and current in amperes. 地球吸引月球,月球也吸引地球 The earth attracts the moon and the moon the earth
1. This equipment, it is said, was commercially available three years ago 4.-1--1, it was agreed, should be replaceable by-1 at will 8. No textbooks available have mentioned this point