数学求平均值公式

简介：What are you looking at? The teacher sprained her foot. I know how to bruise, so I just gave her a massage. Xiao Xiaobai glared at the few classmates who were peeping out of the window and said angrily, and then asked: Why are you joining in the fun? I wonder if someone can come and help Teacher Sun? Well, don’t let the male classmates come, let’s have a female classmate.