Chemical formula and iupac name for cinnamic

To answer this kind of questions you need to do some research (in books, magazines or Internet).

As result of my research this is the

IUPAC name: (2E)-3Phenylprop-2-enoic acid.

The molecular formula is C9H8O2

Or: draw a bencene structure and attach a propenoic acid (you can see the drawing on the attached file).

Determine the  wavelength of light emitted when an electron  in an li2+ ion  makes a transition from an orbital with n  =  6 to an orbital with n  = 5.