Help please, I have no idea how to solve this

Which statement is always true? a negative exponent cannot be part of an expression's numerator. a negative base raised to the power of 2 has a negative value. a negative base raised to the power of 2 has a positive value. any number to the first power is zero.

Measures of the angle of r, 31 s (x+4) t (3x+9)

Evaluate cos2θ for cosθ = square root of 3/2