What is the wavelength, in nm, of radiation with an energy of 2.668 x 10^(-19)j

V=E/h
v  is   the frequency
 h  is  the  planks  constant  which  is 6.626  x10^-34
v  is  therefore [2.668 x 10^-19] /6.626 x10^-34=4.027 x10^14
 c(speed  of  light)=wavelength  x   frequency
 c is always =3.0  x10^8
therefore wavelength  = ( 3.08  x10^8)/4.027 x 10^14=7.649 x10^-7
convert to  nm
=(7.649 x10^-7) x(1.0  x 10 ^9 nm)=764nm