(20)4- Assume you have the following parallel program written using OPENMP. Assume the computer has four cores. Assume it takes 5,20,25, and 30 seconds to execute f1(), f2(), f3 (), and f4 () functions on a single core computer, respectively. How long does it takes to execute following program on a four core computer? \#pragma omp parallel sections num_threads(3) \{ \#pragma omp section a=f1() \#pragma omp section b=f2() \#pragma omp section c=f3() \} d=f4(a+b+c) cout