GMAT数学题 感激不尽：Q4 How many seconds will it take for a car that

GMAT数学题 感激不尽：Q4 How many seconds will it take for a car that is traveling at
请问谁能讲一下为什么
How many seconds will it take for a car that is traveling
at a constant rate of 45 miles per hour to travel a
distance of 220 yards?(1 mile=1,760 yards)
A.8
B.9
C.10
Answer C
Q5
If x^3y^4=5,000,is y=5?
(1)y is a positive integer.
(2)x is an integer.
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A.Statement (1) ALONE is sufficient,but statement (2) alone is not sufficient.
B.Statement (2) ALONE is sufficient,but statement (1) alone is not sufficient.
C.BOTH statements TOGETHER are sufficient,but NEITHER statement ALONE is sufficient.
Answer:C
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