As a method for the synthesis of cinnamaldehyde (3-phenyl-2-propenal), a chemist treated 3-phenyl-2-propen-1-ol with K2Cr2O7 in sulfuric

Question:

As a method for the synthesis of cinnamaldehyde (3-phenyl-2-propenal), a chemist treated 3-phenyl-2-propen-1-ol with K2Cr2O7 in sulfuric acid. The product obtained from the reaction gave a signal at d 164.5 in its 13C NMR spectrum. Alternatively, when the chemist treated 3-phenyl-2-propen-1-ol with PCC in CH2Cl2, the 13C NMR spectrum of the product displayed a signal at d 193.8. (All other signals in the spectra of both compounds appeared at similar chemical shifts.)
(a) Which reaction produced cinnamaldehyde?
(b) What was the other product?