When photon of energy 4.0 eV strikes the surface of a metal A, the ejected photoelectrons have maximum kinetic energy TA eV end de-Broglie wavelength λA. The maximum kinetic energy of photoelectrons liberated from another metal B by photon of energy 4.50 eV is TB=(TA−1.5)eV. If the de-Broglie wavelength of these photoelectrons λB=2λA, then the work function of metal B is :