流行色是指在一定时间范围里，流行于某些地区或国家的（）、时髦色彩。A.时新 B.时髦

波尔多液农药不能用铁制容器盛放，是因为铁能与农药中的硫酸铜起反应，请写出反应的化学方程式______，并指明氧化剂______，还原剂______．

9×______＜50______×4＜22．

润滑油净化系统的作用？

血清总胆红素（TB）的正常参考值为（）。

A.0.7～1.7μmol／L

B.1.5～15.1μmol／L

C.1.7～17.1μmol／L

D.17～34μmol／L

E.34～170μmol／L

Rapid application development (RAD) systems purport to lighten the developer’s (46) by making it easy to program an application with simple intuitive steps.

RAD tools (47) the developer everything needed to construct a fully functional application quickly and easily. They make short work of modifying the developed product to (48) changes after the program is finished. Applications developed with RAD tools are constructed as they are envisioned. As an application’s real usefulness (49) , the developer armed with RAD tools should be able to (50) on new features with little fuss.

（49）是（）

A.appearances

B.emerges

C.recognizes

D.solves