题目

Last winter vacation，some of my classmates decide to travel with their friends，while I chose to take part－time job.I wanted to gain experiences and earn some money.I learned from my teacher that a nearby company was looking after students with good handwriting or write address on envelope The pay were 10 cent per envelope.I headed for the company，feeling sure I would easy finish 300 envelopes in five hours and to earn the money.Actually，I only finished 200.Now，I fully understand how hard is to earn money.Getting out of the classroom is indeed necessary for we all.叙述正确的是 （   ）A．脂肪可被苏丹IV染液染成橘黄色B．用于鉴定蛋白质的双缩脲试剂A和B液要混合均匀后，再加入含样品的试管中，且要现配现用C．鉴定可溶性还原糖时颜色变化：蓝色-棕色-砖红色D．脂肪的鉴定实验中需用显微镜才能看到被染成橘黄色的脂肪滴