There is no equivalence.
A foot is a measure of length or distance while a foot per second is a measure of speed. The two measure different things and, according to basic principles of dimensional analysis, conversion from one to the other is not valid without some addition information.
100 feet per second.
146.6 feet per second.
About 4.55 feet per second.
About 41 feet per second.
5.583 feet per second.
39.6 feet per second.
80.6666667 feet per second
77.73 feet per second.
It is about 36.6 feet per second.
44 feet per second.
About 2.3 feet per second.
85.0666667 feet per second