If the Wave Function for a Free Electron Is Given

Multiple Choice

If the wave function for a free electron is given by Ψ = A sin kx + B cos kx, and the electron has a kinetic energy of 9.0 eV, what is the value for k?

A) 2.5 x 10⁹ m^-1
B) 1.0 x 10¹⁰ m^-1
C) 1.5 x 10¹⁰ m^-1
D) 4.5 x 10¹⁶ m^-1
E) 9.7 x 10¹⁷ m^-1