| A | B |
| elastic | having the quality of returning to its original size |
| elasticity | elastic quality |
| detect | discover in the performance of some act |
| detection | a finding out |
| alternate | arrange, do or perform each after the other continuously |
| alternative | choice from among two or more things |
| economy | management of affairs and resources of a country area |
| economics | science of the production, distribution, and consumption of goods and services |
| normal | of the usual standard |
| normality | normal condition |
| concentrate | bring together in one place |
| concentration | concentrating |
| initiate | be the first one to start |
| initiative | active part in taking the first steps in any undertaking |
| restore | bring back |
| restoration | a restoring |
| evaluate | find out the value or the amount of |
| evaluation | an evaluating |
| office | place in which the work of a position is done |
| official | having authority |