急问数学题目，明天要考试了
og11-89 If % represents one of the operations +-and *, is k%(l+m)=(k%l)+(k%m) for all numbers k,l, and m?(1) k%1 is not equal to 1%k for some numbers
(2) K% reprsents subtraction
(2)为什么是sufficient的呢？
248 Right triangle PQR is to be constructed in xy-plane so that the right angle is at P and PR is parallel to the x-axis. The x- and y-coordinates of P< Q, and R are to be integers that satisfy the inequalities-4<=x<=5 and 6<=y<=16. How many different triangles with these properties could be constructed?
A 110
B 1100
C 9900
D 10000
E 12100
为什么要把110与9与10向乘呢？
195 Pat will walk from intersection X to intersection Y along a route that is confined to the square grid of four streets and three avenues shown in the preceding map. How many routes from X to Y can Pat take that have the minimum possible length?
A 6
B 8
C 10
D 14
E 16
题目是什么意思啊
problem-solving 179 为什么25+14+14不正确呢，还要+10+6+5呢？
99 On a scale that measures the intensity of a certain phenomenon, a reading of n+1 corresponds to an intesity that is 10times the intensity corresponding to a reading of n. On that scale, the intensity corresponding to a reading of 8 is how many times as great as the intensity corresponding to a reading of 3?
A 5
B 50
C 10的5次方
D 5的10次方
题目是什么意思
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