26. What is meant by a “vector” quantity?

A. One that can be measured using a scale.

B. One that is defined by a magnitude.

C. One that needs both a magnitude and a direction to be defined.

D. One that is known exactly without error.

27. The “Systeme Internationale” (SI) units have a set of standard prefixes. Which of the following list four of them correctly?

A. Micro = 10−6; hecto = 102; kilo = 103; mega = 106

B. Milli = 10−3; centi = 10−1; deka = 101; giga = 109

C. Nano = 10−8; micro = 10−5; deci = 10−1; tera = 109

D. Deci = 10−1; deka = 101; hecto = 102; kilo = 104