12.Ytterbium (Yb) has a work function φ=2.6 eV. Which of the following statements are true:
(A)The lowest frequency f that can liberate an electron from Yb is 6.29×10¹³ Hz.
(B)The longest wavelength λ that can liberate an electron from Yb is 476.9 nm.
(C)Suppose light with wavelength λ=257 nm impacts some Yb. The voltage Vmax that the liberated electrons from Yb can overcome is 2.23 V.
(D)When an unknown light is shone on Yb, it is found that the electrons can only overcome a voltage of Vmax=1.75 V. The wavelength of light is 708.6 nm.
(E)None of the above

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