What is the name of this definition: “It punishes for something that was not illegal when it was done”?

During the end of the 19th century and the early 20th century the was becoming one of the most popular instruments in america? banjo fiddle guitar pianola (player piano) tambourine

What project establish leonardo da vincis reputation as a creative and talented engineer

Which two objectives does the international monetary fund (imf) address? a -creative stability b-allowing fluctuations in currency exchangec-reducing poverty in developing countriesd- segrating nations as industrial and agriculture economicse- promoting protectionism in trade