Which expression is equivalent to RootIndex 3 StartRoot 256 x Superscript 10 Baseline y Superscript 7 Baseline EndRoot? 4 x squared y (RootIndex 3 StartRoot x squared y cubed EndRoot) 4 x cubed y squared (RootIndex 3 StartRoot 4 x y EndRoot) 16 x cubed y squared (RootIndex 3 StartRoot x y EndRoot) 16 x Superscript 5 Baseline y cubed (RootIndex 3 StartRoot y EndRoot)