题目

小刚在做探究欧姆定律的实验。 （1）在“研究电流跟电压的关系”时，他连接的电路如图所示。但电路中有一根导线接错了，请你用笔在图中将接错的导线打上“×”，并画出正确的接线。 （2）在“研究电流跟电阻的关系”时，小刚把定值电阻由5换成10，闭合开关后，下一步应怎样操作?  （3）图是小刚在科学探究过程中，根据实验数据绘制的图像。 观察甲图得出的结论是：                                                �阅读下列对话，选择正确的答案。Mary: Do you have black bags?Mr Green: Yes, I do.I have black bags, red bags and blue bags.Do you like these?Mary: Yes, I do.How much are they?Mr Green: They are thirty dollars.Mary: Do you have pants?Mr Green: Yes, I do.These red pants are seven dollars.Mary: How much are those pants on the table?Mr Gteen: Seventeen dollars. And those black pants are twelve dollars.Mary: I'll take these red pants.1.They________ white bags.A. have    B. don't haveC. aren't D. are have2. The bags are________.A.￥20    B. $13C.￥13    D. $303.Mary ________ the bags.A. like       B. don't likeC. likes D. doesn't like4.The black ________ are $12.A. bags    B. shortsC. pants D. shoes5.Which ones are cheap?A. The red bags.  B. The blue bags.C. The red pants.  D. The black Dants.