法洛四联症不会出现的是（） ["苍白","晕厥","蹲踞","青紫","活动耐力下降"]
截瘫患者利用腋杖步行时，不包括（） ["两点步行","三点步行","四点步行","五点步行","同时拖地步行"]
脑性瘫痪肌张力测定不包括（） ["头背屈曲","臂弹回试验","内收肌角","围巾征","儿童智力发育迟滞"]
脑性瘫痪的临床表现不包括（） ["剪刀步态","尖足","运动过度","痉挛","手-口-眼协调"]
有氧运动训练时，下列哪项不提示运动强度过大（） ["不能完成运动","活动时因气喘不能自由交谈","运动后有轻度的疲劳感","运动后出现明显无力","运动后出现恶心"]
1．何谓经济寿命？
2．如何根据磨损方程计算磨损寿命？
