she and her husband discovered that hemoglobin carries oxygen
The most impressive thing she did was probably winning a record of 5 Grammy Awards in one night.
he shreds at the guitar!
I once threw a football over 50 yards in a game, which was the most impressive thing I've ever thrown into the air.
The applicant can look at what the employer includes in the job posting.
The answer is Ishtar. It was one of the 8 gates into Babylon and the most impressive.
Asian Art: The most impressive surviving oriental artifacts.
Read the introductory article in Wikipedia - or the complete article. One thing that's important to note is that energy is a conserved quantity; the definition can be a bit abstract. Quoting from the Wikipedia article: 'The question "what is energy?" is difficult to answer in a simple, intuitive way, although energy can be rigorously defined in theoretical physics.' You'll have to decide for yourself which definition you find most "impressive"; the most impressive definition is probably not the most accurate one.
Elizabeth 1 and Henry VIII are both impressive.
NOTHING
Parthenon
parthenon
Ishtar.