Prompt analysis
A and b are real numbers.
Superset
The answer will be either YES or NO.
Translation
In order to find the answer, we need:
1# exact value of a and b.
2# any equation to find the a and b
3# any equation to find the exact or the range for a/b
Statement analysis
St 1: a^2/b^3 >0. a^2 is always greater than zero. If the complete expression is positive, that means that b^3 is positive hence b is positive. But nothing can be said about a. INSUFFICIENT
St 2: ab^4<0. b^4 is always positive.nothing can be said about b though. To make the expression negative, a has to be negative.
St 1 & St 2: from st 1, we can say that b>0. From st 2, we can say that a<0. Therefore a/b <0.
Option C.
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