【简答题】已知AB是⊙O的直径,弦AC平分∠BAD,AD⊥CD于D,BE⊥CD于E。 求证:⑴CD是⊙O的切线; ⑵CD 2 =AD·BE。
【简答题】We often (neglect) _________ to make proper use of our bodies.
【单选题】某轮计划航向020°,航速15kn,无风流中航行,预计利用航线左前方正横距离为5n mile的物标转向,采用正横方位转向,如果用四点方位法来确定转向时机,则应在物标真方位为 时记录第一次观测时间,第一次观测后 时间转向。
【单选题】We often ____ to make proper use of our bodies.
【判断题】It is proper to make use of false information to attain consumers’ interest in advertising.
【单选题】The proper use of pronouns will make an essay more _________.
【简答题】颜色模型有哪几种?试说明RGB、CMYK以及HSV颜色模型各适于在什么情况下应用?