24.- Lovely weather, isn’t it?
- Yes, a bit hot, ______.
A. although B. but C. though D. yet
23. Canada has vast areas of wilderness, from the Arctic north, _______ average winter temperatures are usually -20 0C, to the border with the USA in the south, _______ is said to be the longest border in the world not defended.
A. which, where B. whose, which C. where, where D. where, which
22.. Garter Druse ______ his being selected for the important task to his courage，devotion and knowledge of the area.
A. led B. owed C. devoted D. contributed
第一节 单项填空(共15小题；每小题1分，满分15分)
从A、B、C和D四个选项中，选出可以填入空白处的最佳选项，并在答题卡上将该项涂黑。
21. ______ Flying Luxury Hotel of Tomorrow is ______ huge 400-ton aircraft without wings.
A. /, a B. The, a C. The, the D. A, a
20．(本小题满分12分)函数f(x)对任意的a、b∈R,都有f(a+b)=f(a)+ f(b)-1,并且
当x＞0时，f(x)＞1.
(1)求证：f(x)是R上的增函数；
(2)若f(4)=5,解不等式f(3m2-m-2)＜3.
19．(本小题满分12分)已知集合，函数的定义域为Q，
(1)若，求实数的取值范围；
(2)若方程在内有解，求实数的取值范围.
18．(本小题满分12分)若a,bR,集合求b-a的值.
16(本小题满分12分)已知集合A={x|mx2-2x+3=0，m∈R，x∈R }.
(1)若A是空集，求m的取值范围；
(2)若A中只有一个元素，求m的值；
(3)若A中至多只有一个元素，求m的取值范围.
17．(本小题满分12分)已知，
，函数
的定义域为Q，
，求实数
的取值范围；
在
内有解，求实数
R,集合
求b-a的值.
}. 
，求m的取值范围. 
，
