问题
问答题 简答题
说明吹灰系统中THUMBEEL SWTTCHES手轮开关的作用。
答案
参考答案：
长伸缩式和墙式吹灰器各有一个手轮开关，每个开关有两个功能：
（1）用来与ENABLE／DISABLE两个按钮相配合，使各个单独的吹灰器能或不能投入运行；
（2）用来与MANUALSTART按钮相配合，使各个单独的吹灰器能运行。
搜题请搜索小程序“爱下问搜题”
说明吹灰系统中THUMBEEL SWTTCHES手轮开关的作用。
参考答案：
长伸缩式和墙式吹灰器各有一个手轮开关，每个开关有两个功能：
（1）用来与ENABLE／DISABLE两个按钮相配合，使各个单独的吹灰器能或不能投入运行；
（2）用来与MANUALSTART按钮相配合，使各个单独的吹灰器能运行。
| The most popular organic gem is the pearl. A pearl is the response of a marine mollusk to the presence of an irritating impurity accidentally introduced into its body; a cultured pearl is the result of the intentional insertion of a mother-of-pearl bead into a live mollusk. Whether introduced accidentally or intentionally, the pearl-making process is the same: the mollusk coats the irritant with a substance called nacre. Nacre is composed chiefly of calcium carbonate. Because very few natural pearls are now on the market, most pearls used in free jewelry are cultured. These include "Biwa" pearls and most other freshwater pearls. Cultured pearls are not easily distinguished from natural pearls except by an expert. |
Cultured pearl is formed by ______.
A．insertion of a pearl into a live mollusk
B．an oyster into which a piece of grit has been placed
C．putting in a live mollusk
D．placing a bead into culture