Question

Can someone check my answers please?

Answer 1

The Potsdam Declaration:

threatened the use of the atomic bomb<--my answer

secured Hirohito's position as emperor

threatened "prompt and utter destruction"

called the Soviets into the Pacific War

Answer 2

Your answer is valid, though not correct. In the actual declaration, the US mentioned nothing of the atomic bombs they would use, but they did warn that there would be "prompt and utter destruction".