—Look! How _________ the market is!—Yes. There are always lots of people buying things there.
A:live
B:living
C:alive
D: lively
已知复数z=(1+i)(1+2i),其中i是虚数单位,则z的模是____.
____ ____my friends in Australia some ____ things.
第1个等式:x1= 11×3=12(1−13) ;第2个等式:x2= 15×3=12(13−15) ;
第3个等式:x3= 15×7=12(15−17) ;第4个等式:x4= 19×7=12(17−19) ;
则xl+x2+x3+…+x10=____.