2022高中英语周报牛津版必修4第39期答案

19.解:(1)设“甲闯关成功”为事件A,P(A)- CCi+C-2(4分)2依题意x一B(3)X可能取的值为02,3P(X=0)=C(1P(X=1)=C3(1-3)-影P(X=2)=C()(1-3)==3P(X=3)=C(})所以X的分布列为X0834279229(10分)E(X)=0×8+1×12+2×6+3×127=1(或E(X)=np=3×÷=1)(12分)

One possible versionThen I wondered whether the man would still be at the same spot. I walked out the doorand back to the street where I had met him. There the man was, at the same spot, knees curledup against his chest, with the same cardboard sign shading his head. I walked down the street,and before I could think twice, I stood before him. He cautiously glanced in my direction.Ismiled and held up the lunch bag. "I brought you some lunch, "I saidI handed him the bag, and he looked closely at it. " Thank you for this. I was praying thismorning, asking for someone,s heart to open. We talked for a little while. As he shared hisstory, there was an, open, honest tone in his voice. There was something about giving thatmade me feel like I was talking with a brother. "I hope you have a nice day, "I told him<"Thank you! It's already gotten a lot better, " he said. As I walked by, his thank fulness hadbecome mind. My day, too, had already gotten a lot better. Anything helps, indeed

以上就是2022高中英语周报牛津版必修4第39期答案，更多英语周报答案请关注本网站。