鳃是动物的呼吸器官。关于鳃的叙述，正确的是（）A.凡水生动物都用鳃呼吸B.有的鳃...

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【单选题】

鳃是动物的呼吸器官。关于鳃的叙述，正确的是（）

凡水生动物都用鳃呼吸

有的鳃在空气中也能发挥气体交换的作用

鳃是皮肤进化而来的呼吸专门器官

只有鱼纲动物才有真正的鳃

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Store the workload file on SQL1. Start DTA on SQLtest and connect to SQL1. Specify all workload and tuning options as necessary. In the Advanced Tuning Options dialog box， select the Generate only online recommendations check box.

Store the workload file on SQLtest. Start DTA on SQLtest and connect to SQLtest. Specify all workload and tuning options as necessary. In the Advanced Tuning Options dialog box,select the generate only online recommendations check box.

Store the workload file on SQL1. Start DTA on SQL1 and connect to SQL1. Specify all workload and tuning options as necessary. In the Advanced Tuning Options dialog box，select the All recommendations are offline check box.

Store the workload file on SQLtest. Start DTA on SQLtest and connect to SQLtest.Specify all workload and tuning options as necessary.In the Advanced Tuning Options dialog box,select the All recommendations are offline check box.

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GNP

GDP

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NFP

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圆柱外螺纹与圆椎内螺纹连接

圆椎外螺纹与圆椎内螺纹连接

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正确

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