Wording help please?

Hi,

Could you please check for me If I am correct for the meaning of these two words?

Identify - discovery or find out

Police tried to [ identify / determine ] who was a killer from these suspects. (Both words are correct however "identify" is more accurate meaning for it?)

Scientist tried to [ identify / determine ] the link between diet and cancer. (Same as above)

It was [ identified / determined ] that he had died of natural causes. (Same as above)

Determine - official decision or firm decision.

I am [ determined / resolved ] to finish my research. (Both words are correct however "determined" is more accurate meaning for it?)

A date for the meeting has not be [ determined / resolved ]. (Same as above)

The court [ determined / resolved ] that the defendant should pay the legal costs. (Same as above)

I made a [ determination / resolution ] to finish my research. (Same as above)

He is a [ determined / resolute leader ]. (Same as above)

Cheers