Page 4 - FOKUS STRATEGI SAINS 4 焦点攻略科学4

第 6 课 声音.....................................................................................................55

. ..声音...................................................................................................... 56
练习 6 Quick Quiz ......................................................................................61

第 7 课 能 .................................................................................................63

. ..能的来源和形式.................................................................................. 64
. ..不可更新和可更新的能源................................................................... 70
练习 7 Quick Quiz ..................................................................................... 73

主题四 材料科学

第 8 课 材料..................................................................................................... 77

. ..材料的来源.......................................................................................... 78
. ..材料的性质.......................................................................................... 82
练习 8 Quick Quiz ..................................................................................... 87

主题五 地球与宇宙
第 9 课 地球......................................................................................................91

..地心引力.............................................................................................. 92
. 焦点攻略科学4, 版权所有·侵权必究
. ..地球的转动.......................................................................................... 94
练习 9 Quick Quiz ..................................................................................... 96

主题六 工艺与优质生活

第 10 课 机械.....................................................................................................98

. ..杠杆...................................................................................................... 99
. ..简单机械和复杂机械..........................................................................101
练习 10 Quick Quiz ..................................................................................105

答案.................................................................................................................... 109

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