Which question could be answered through modeling but not through experimentation? How does UV light affect protein structure?

At what rate is global warming?

What is the minimum level of carbon monoxide detected by a carbon monoxide detector?

Which material that is used in running shoe soles is most likely shock-absorbent?

rate of global warming

Explanation: all others involve directly measurable factors.

the truman doctrine was an american foreign policy whose stated purpose was to counter soviet geopolitical expansion during the cold war. it was announced to congress by president harry s. truman on march 12, 1947, and further developed on july 12, 1948, when he pledged to contain threats to greece and turkey.