定义在R上的函数$f\left(x\right)$既是偶函数又是周期函数，若$f\left(x\right)$的最小正周期是$\pi$，且当$x\in 0,\frac{\pi }{2}$时，$f\left(x\right)=\sin x$，则$f\left(\frac{5\pi }{3}\right)$的值为（   ）

下列高原与地形地貌特点的组合，正确的是（    ）

先通读下面的短文，掌握其大意，然后从A、B、C、D四个选项中选择可以填入空白处的最佳答案．

    Online shopping is very easy for young people，but it's difficult for old people．Some Daigou shops，or buy-for-your shops,are1them much.

    Mr Li,a 64-years-you old man,is2his favourite CD in Daigou shop.He says,It's very convenient(方便的)to buy things online，but I can't 3the Internet．I'm lucky to find this buy-for-you shop，as I4to buy an opera CD．I am so happy to get5．From now on，I  6going to look for more things．”A manager of the shop says，“To meet(满足)the needs  7people，I start 8shop．”0ther people9find the large needs in Daigou shops．In many cities，such shops are opening their doors．

    Daigou shops are10for people to shop．

淀粉、蛋白质、脂肪在消化道内开始消化的正确顺序是（　　）