A、F=AB
B、<IMG src="https://s3.cn-north-1.amazonaws.com.cn/qingshuxuetang/staticQuestionImg/94a26734-7aa1-4cc1-99d6-e1e3497f230e.jpg"title="ex_1426746507162_0.jpg" alt="ex_1426746507162_0.jpg"/>
C、<IMG src="https://s3.cn-north-1.amazonaws.com.cn/qingshuxuetang/staticQuestionImg/dd62b9e6-58ed-45eb-ad74-3dcfb85d7aea.jpg"title="ex_1426746523670_0.jpg" alt="ex_1426746523670_0.jpg"/>
D、F=A+B