分式 $\frac{2x\text{-4}}{x+3}$ 的值为0，则x的值为____.

研究发现高血压患者常出现胰岛素利用障碍，从而导致糖尿病．服用降压药物﹣血管紧张素转换酶抑制剂（ACEI）可在一定程度上降低血糖．相关分析正确的是（　　）

    Little Red Riding Hood lives near a forest (森林). She often goes to visit her grandma. She usually brings her some food. One day, when she is on her way to her grandma's home, a wolf sees her. The wolf stops her and asks, “Where are you going?” “My grandma's home.” answers Little Red Riding Hood. The wolf suggests (建议）picking some flowers for her grandma. The wolf runs to her grandma's home first. He eats the grandma. He is lying (躺）in the grandma's bed. Little Red Riding Hood comes and the wolf wants to eat her. Little Red Riding Hood cries for help. A hunter (猎人）comes quickly. The wolf is afraid, and he runs away.

a、如图甲，将毛巾铺在水平木板上，让小车从斜面顶端由静止滑下，观察小车在水平面上通过的距离．

b、如图乙，取下毛巾，将棉布铺在斜面和木板上，让小车从斜面顶端由静止滑下，观察小车在水平面上通过的距离．

c、如图丙，取下棉布，让小车从斜面顶端由静止滑下，观察小车在水平面上通过的距离．

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