题型:问答题 简答题 Passengers on board aren't allowed _____ calls during take-off.A.making or receivingB.to make or receiveC.to have made or receivedD.having made or received 查看答案
题型:问答题 简答题 计算:(1)-32×0÷3-2+|-27|(2)(2x2y)3-(-7xy2)÷(14x4y3)(3)(x-5)2-(x-2)(x-3)(4)[(a+b)(a-b)+(a+b)2-2a2]÷(-2a) 查看答案