Please help for below questions.

Metal has complex refractive index. The real part ne (or n) is the refractive index and indicates the phase velocity, while the imaginary part ny (or k) is called the extinction coefficient. Find refractive index of copper (Cu) from webpage https://refractiveindex.info/ , estimate the reflectance spectrum of copper mirror at normal in the wavelength range from 300nm to 1 um and draw the spectrum. (Hint: you need to read the real and imagery refractive index at different wavelengths and calculate the reflectance.)