a.5
b.10
c.15
d.20
e.25 ANS:D
47.If (1/5)^m*(1/4)^18=1/2(10)^35 then m=
a.17
b.18
c.34
d.35
e.36 ANS:D
48.If xy+z=x(y+z),which of the following must be true?
a.x=0 and z=0
b.x=1 and y=1
c.y=1 and z=0
d.x=1 or y=0
e.x=1 or z=0 ANS:E
49.For a finite sequence of nonzero numbers, the number of variations in sign is defined as the number of pairs of consecutive terms of the sequence for which the product of the two consecutive terms is negative. What is the number of variations in sign for the sequence1,-3,2,5,-4,-6?
a.one
b.two
c.three
d.four
e.five ANS:C
70.The cost to park a car in a certain parking garage is $8.00 for up to 2 hours of parking and $1.75 for each hour in excess of 2 hours. What is the average cost per hour to park a car in the parking garage for 9 hours?
a.$1.09
b.$1.67
c.$2.25
d.$2.37
e.$2.50
請問這幾題是什麼意思啊
我有看沒有懂的說
請各位高手相助
謝謝
