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\*.

where did the first civilization in africa start
Kingdom of Kush

when were air brakes first used on trucks
the early 20th century

who sang the theme from the greatest american hero

American singer Joey Scarbury