please write it on C language and use function to solve it

Task: The table below shows the normal boiling points of several substances. Write a program that prompts the user for the observed boiling point of a substance in C and identifies the substance if the observed boiling point is within 5% of the expected boiling point. If the data input is more than 5% higher or lower than any of the boiling points in the table, the program should output the message Substance unknown. Your program should define and call a function within_ x percent that takes as parameters a reference value ref, a data value data, and a percentage value x and returns 1 meaning true if data is within x% of ref-that is, (ref x% * ref)