Gravitational firce and speed,light i guess. LOL im not even sure is this is right
Anything bigger than 5 you round up, anything lower than 5 you round down. the number you determine this by is the number behind the decimal. using your number 25.691 which means you would round up the 6 and have the number 26.000 as the final answer. if it was for say 25.400 your number would end up being 24.000.
Temporary, not permanent, short-term, ect