1.what should be multiplied to 4x²y³z to get -16x⁴y³z³
a.4x²y²z b.4x²yz²
c.-4x²z² c.-1/4x²z²

2.which of the following is a difference of two squares?
a. x²-2 c.x⁴y⁵-100
b2x²-16 d.9x⁶y⁴-64

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