对于亲合力较差、成活较难的树种进行嫁接繁殖，一般采用的嫁接方式为（）。A、切接 B、 发布时间：2017-06-27 03:54 │ 来源：www.tikuol.com 题型：单项选择题 问题： 对于亲合力较差、成活较难的树种进行嫁接繁殖，一般采用的嫁接方式为（）。A、切接B、劈接C、靠接D、插皮接
题型：单项选择题 完形填空 Children in Britain have 14 weeks of school holidays every year. The three main holidays are duringthe summer, at Christmas and Easter(复活节). But they 1 have a week off for half-term in Februaryand October. Every February and October, school children in the UK have a week off to relax from school. Thisweek is half-term. There is nothing 2 to celebrate at half-term. Children spend this time 3 funand catching up on schoolwork. 4 children hang out with friends, go swimming, visit museums orsee relatives. They only have a small amount of schoolwork to do over the 5 . They may be 6 to revise(复习) for a test or complete some schoolwork by their teachers. 7 the main purpose(主要目的) is to let them relax and pursue(追求) their 8 . During the summer holidays, quite a fewfamilies go away on a mini-break. Many people travel to 9 cities in Britain and some families areeven 10 to go to Europe. Popular holiday places include France, Italy and Spain.( )1. A. also ( )2. A. especially ( )3. A. have ( )4. A. Few ( )5. A. terms ( )6. A. asked ( )7. A. Because ( )8. A. subjects ( )9. A. another ( )10.A. lucky enoughB. too B. especial B. having B. None B. holidays B. made B. Still B. jobs B. the others B. enough luckyC. either C. special C. to have C. Most C. half-termsC. forced C. But C. hobbies C. others C. too luckyD. both D. speciallyD. had D. No D. festivalsD. allowed D. Though D. tests D. other D. so lucky 查看答案
题型：单项选择题 已知25 ℃时,AgCl的溶度积Ksp=1.8×10-10,则下列说法正确的是( )A．向饱和AgCl水溶液中加入盐酸,Ksp变大B．AgNO3溶液与NaCl溶液混合后的溶液中,一定有c(Ag+)=c(Cl-)C．温度一定时,当溶液中c(Ag+)·c(Cl-)=Ksp时,此溶液中必有AgCl的沉淀析出D．将AgCl加入到较浓的KI溶液中,部分AgCl转化为AgI,因为AgCl的溶解度大于AgI的 查看答案
×108 m/s，若使光由空气射入这种玻璃，且使折射光线与反射光线垂直，则入射角应是（ ）