烤房每100竿烟需要地洞面积为（）㎡
A、0.10—0.12
B、0.18—0.24
C、0.24—0.35
D、0.36—0.48
参考答案：A
When _____ help, one often says "Thank you" or "It's kind of you".[ ]
A. offering
B. to offer
C. to be offered
D. offered
一般说来腐殖质的吸附能力（）
A、比粘土矿物强
B、比粘土矿物弱
C、与粘土矿物几乎相同
D、比原生矿物强
