formula n.【1a fixed arrangement of words, esp. as used on social, legal or ceremonial occasions【2a group of letters, numbers, or other symbols which represents a scientific or mathematical rule【3a method, plan, or a set of principles worked out to achieve a desired resultAccording to Einstein’s formula E=mc2, any given amount of mass is equivalent to a certain amount of energy, and vice versa.
A.a fixed arrangement of words, esp. as used on social, legal or ceremonial occasions
B.a group of letters, numbers, or other symbols which represents a scientific or mathematical rule
C.a method, plan, or a set of principles worked out to achieve a desired result
D.null
正确答案：a group of letters, numbers, or other symbols which represents a scientific or mathematical rule