Given That the Observed Absorption Maximum for the Complex Ion $\Delta$

Given that the observed absorption maximum for the complex ion CoF₆^3- in solution is
$\Delta$ _max = 700 nm, what is the value of the crystal field splitting, $\Delta$ _o?

A) 2.8 *10^-19 J
B) 2.8 * 10^-28 J
C) 7.2 * 10³⁰ J
D) 3.2 *10^-36 J
E) 7.2 * 10^-19 J