出几道题，看看能答对多少

    下面3个命题，哪个（些）是永假命题(永远返回false)：

bool QuestionAboutDouble(double x, double y)

{

return x.Equals(y) && x != y;

}

bool QuestionAboutType(int[] x)

{

if (x == null)

return false;

return x.GetType() != typeof(int[]);

}

bool QuestionAboutInt(int x)

{

for (int i = 0; i < 100; i++)

x = x + x;

return x < 0;

}

.csharpcode, .csharpcode pre
{
font-size: small;
color: black;
font-family: consolas, "Courier New", courier, monospace;
background-color: #ffffff;
/*white-space: pre;*/
}
.csharpcode pre { margin: 0em; }
.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
.csharpcode .str { color: #006080; }
.csharpcode .op { color: #0000c0; }
.csharpcode .preproc { color: #cc6633; }
.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
}
.csharpcode .lnum { color: #606060; }

 

    下面一道题的返回值是多少：

int QuestionAboutClosure()

{

int x = 0;

Func<int>[] funcs = new Func<int>[10];

for (int i = 0; i < 10; i++)

funcs[i] = () => x += i;

(from f in funcs select f()).Count();

return x;

}

.csharpcode, .csharpcode pre
{
font-size: small;
color: black;
font-family: consolas, "Courier New", courier, monospace;
background-color: #ffffff;
/*white-space: pre;*/
}
.csharpcode pre { margin: 0em; }
.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
.csharpcode .str { color: #006080; }
.csharpcode .op { color: #0000c0; }
.csharpcode .preproc { color: #cc6633; }
.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
}
.csharpcode .lnum { color: #606060; }