| 摘要 |
<p>The educational exercise device can be used both in class and for self study. Operation of one of two rows of switches selects one of several fixed stored programmes. Answers to the corresponding exercises in a book are selected from an array of metallic contacts with a pen. A correct answer is indicated by a green light and an incorrect answer by a red light. A LED or LCD display shows the total number of correct and incorrect answers for the selected programme. Successive attempts at one exercise, which must be answered correctly before the next exercise is begun, are not registered on the display.</p> |
