大N大N帮帮我，快考试了，求解若干数学题

7.
                905-!-item-!-187;#058&000575   (e)

For every positive even integer n, the function h(n) is defined to be the product of all the even integers from 2 to n, inclusive.  If p is the smallest prime factor of h(100) + 1, then p is

(A) between 2 and 10

(B) between 10 and 20

(C) between 20 and 30

(D) between 30 and 40

(E) greater than 40

33.       4484-!-item-!-187;#058&004004

If x^4 + y^4 = 100, then the greatest possible value of x is between

(A) 0 and 3

(B) 3 and 6

(C) 6 and 9

(D) 9 and 12

(E) 12 and 15

答案是B ，
            我选的是A 。X 不是应该小于4 的吗? 4^4 > 100

] 72.    8363-!-item-!-187;#058&005969

A thin piece of wire 40 meters long is cut into two pieces.  One piece is used to form a circle with radius r, and the other is used to form a square.  No wire is left over.  Which of the following represents the total area, in square meters, of the circular and the square regions in terms of r ?

(A) 

(B) 

(C) 

(D) 

(E) 

题目不全，
            哪位大侠帮忙补一下
            

还有最后叫求的是笔试正方形和园的面积吗？in square meters, of the circular and the square regions in terms of r ?
            作何理解？
            

149.     15609-!-item-!-187;#058&010412   b

A certain library assesses fines for overdue books as follows.  On the first day that a book is overdue, the total fine is $0.10.  For each additional day that the book is overdue, the total fine is either increased by $0.30 or doubled, whichever results in the lesser amount.  What is the total fine for a book on the fourth day it is overdue?

(A) $0.60

(B) $0.70

(C) $0.80

(D) $0.90

(E) $1.00
                

怎么算都是0.8 方案一
            分别为 0.1  0.4 0.7 1.0；方案二：0.1  0.2  0.4  0.8

173.     18259-!-item-!-187;#058&011463

In a certain state, gasoline stations compute the price per gallon p, in dollars, charged at the pump by adding a 4 percent sales tax to the dealer's price per gallon d, in dollars, and then adding a gasoline tax of $0.18 per gallon.  Which of the following gives the dealer's price per gallon d in terms of the price per gallon p charged at the pump?

题目看不懂，谁能解释一下？
            

175.     18356-!-item-!-187;#058&011490

Before being simplified, the instructions for computing income tax in Country R were to add 2 percent of one's annual income to the average (arithmetic mean) of 100 units of Country R's currency and 1 percent of one's annual income.  Which of the following represents the simplified formula for computing the income tax, in Country R's currency, for a person in that country whose annual income is I ?

答案是
                50 +I/40

题目看不懂，谁能解释一下？
            

123.     12975-!-item-!-187;#058&009772

When positive integer n is divided by 3, the remainder is 2; and when positive integer t is divided by 5, the remainder is 3.  What is the remainder when the product nt is divided by 15 ?

(1) n - 2 is divisible by 5.

(2) t is divisible by 3.

费费
            

有三个队每对派出三个人参加一个比赛，如果一对中一个人最后的了N名，那么这个队就得了6-N 分，1<=N<=5,没有平局，如果没有一个队超过6分，文三队中最低得分可能是多少？
            

答案是3.

1、【思路】
                            

      假設h(100)+1最小因數是 n , n<50
例如47好了, 既然47是因數, 他就能整除h(100)+1
可是發現h(100)裡面有47的因數,可以整除
                那h(100)+1被47除的餘數為1,表示47不是h(100)+1的因數
                    
同理去想
                小於50的其它因式
                也是會一樣的結果
                    
所以h(100)+1的因式是在
                大於50外

重點在那50!, 假如
                小於50的質數是h(100)的factor,那就不會是h(100)+1的factor ,因為餘數會是1

答案是B ，
            我选的是A 。X 不是应该小于4 的吗? 4^4 > 100

不能这么想

根据题目要求，X最大时肯定是X^4=100，那么就是求X的区间，3^4=81;4^4=256,那么肯定在【3，4】这个区间了，所以选B

不能这么想

根据题目要求，X最大时肯定是X^4=100，那么就是求X的区间，3^4=81;4^4=256,那么肯定在【3，4】这个区间了，所以选B

A thin piece of wire 40 meters long is cut into two pieces.  One piece is used to form a circle with radius r, and the other is used to form a square.  No wire is left over.  Which of the following represents the total area, in square meters, of the circular and the square regions in terms of r ?

(A)  πr²

(B)  πr² + 10

(C)  πr²+ 1/4π²r²

(D)  πr² + (40 - 2πr)²

(E)  πr² + (10 – 1/2πr)²

4、方案一，0.1，0.2，0.4，0.8

   方案二， 0.1，0.4，0.5，0.7

所以选B

Before being simplified, the instructions for computing income tax in Country R were to add 2 percent of one's annual income to the average (arithmetic mean) of 100 units of Country R's currency and 1 percent of one's annual income.  Which of the following represents the simplified formula for computing the income tax, in Country R's currency, for a person in that country whose annual income is I ?

 答案是
                        50 +I/40

 答案是
                50 +I/40

题目看不懂，谁能解释一下？
        

7.

【答案】C

【思路】

n=3x+2
t=5y+3

nt =15xy+10y+9x+6

(1) n-2 = 5a => 3x+2-2 = 5a => 3x is divisible by 5 => n=15b+2
(2) t = 5c => 5y is divisible by 3 => t=15d+3

(1)+(2)

nt = 15Z + 6

Thankyou so much!!!

   恕我愚钝

方案二， 0.1，0.4，0.5，0.7

怎么算的啊，不是按照0.3递增吗？

For each additional day that the book is overdue, the total fine is either increased by $0.30 or doubled, whichever results in the lesser amount

方案一，0.1，0.2，0.4，0.8

方案二， 0.1，0.4，0.5，0.7

0.7=0.4+0.3