下列实验操作中,正确的是
An advertisement uses words and pictures to ____ people to buy a product or service, or to believe in an idea.
被本初子午线穿过的大洲是( )
“爆竹声中一岁除,春风送暖入屠苏。”这首诗描写的是( )
在Rt△ABC中,∠C=90°,sinA=45,则cosB的值等于( )