I am not afraid of tomorrow, ______ I have seen yesterday and I love today.
A:so
B:and
C:for
D:but
元素在自然界有35Cl和37Cl两种同位素,在以下关于计算式34.969x75.77%+36.966x24.23%=35.453说法中正确的是:( )
有氧运动如散步、慢跑、做操等,是科学有效的健身方式.(判断对错)