In this task, You are given an open-domain question that can be answered based on factual information. Your task is to provide \*short\* answer (in a few words only) for the given question. The short answer can be one or more entities or it can also be boolean \*yes\* or \*no\*.

who proposed the modern model of the solar system
Victor Safronov

when did fifty shades of grey movie come out
February 13, 2015

when was under god added to the pledge of allegence

Flag Day 1954