C++ please

Complete the definition of a function called rangeSum that computes the sum of all integers in a range beginning startNum and ending with end- Num. [10 points) H. (a) Define the function given its specifications below. * Computes the sum of all integers between the specified * numbers, inclusive. Assume startNum is less than or equa * to endNum * Gparam startNum the first number in the sequence * Oparam endNum the last number in the sequence *Oreturn the sum of all integers from startNum to endNum (b) Give a statement that calls the function to compute the series 5+ 6+7+ . +100 and displays its return value