The threshold frequency for a photoemissive surface. If J is 4.0 x 10¹⁴ hertz. What is the work function of this?
A) 1.2 x 10–¹⁹J
B) 2.6 x 10–¹⁹ J
C) 6.0 x 10¹⁴ J
D) 6.1 x 10⁴⁷ J