A:人在整个绳索上运动可看成是匀速圆周运动
B:可求得绳索的圆弧半径为104m
C:人在滑到最低点时对绳索的压力为570N
D:在滑到到最低点时人处于失重状态
①胚泡植入子宫内膜
②细胞分裂和分化形成胚胎
③在输卵管处形成受精卵
④初具人形,形成胎儿
⑤胎儿发育成熟、分娩
⑥受精卵分裂、形成胚泡
Tom had to______ the invitation to the party last weekend because he was too busy.