Code:#include <stdio.h> void calcsubtotal(int days, double rate, double food, double* totalFood, double* totalRate) { *totalFood = days * food; *totalRate = (days - 1) * rate; } void calctotal(int days, double airfare, double ground, double rate, double food, double enter, double* totalF, double* totalR, double* total) { double totalFood; double totalRate; calcsubtotal(days, rate, food, &totalFood, &totalRate); *total = totalFood + totalRate + airfare + ground + enter; *totalF = totalFood; *totalR = totalRate; } void output(int days, double airfare, double ground, double rate, double food, double enter, double totalF, double totalR, double total) { printf("\nDays: %d\n", days); printf("Airfare: %.2lf\n", airfare); printf("Ground Transportations: %.2lf\n", ground); printf("Hotel: %.2lf\n", totalR); printf("Food: %.2lf\n", totalF); printf("Entertainment: %.2lf\n", enter); printf("\n"); printf("Total: %.2lf\n\n", total); } void getData(int* days,double* airfare, double* ground, double* rate, double* food, double* enter) { printf("how many days: "); scanf("%d", days); printf("How much is the airfare: "); scanf("%lf", airfare); printf("How much is the ground fare: "); scanf("%lf", ground); printf("How much is the hotel rate: "); scanf("%lf", rate); printf("How much is the food price: "); scanf("%lf", food); printf("How much is the cost of entertainment: "); scanf("%lf", enter); } int main(void) { int days; double airfare; double ground; double rate; double food; double enter; double totalF; double totalR; double total; double subtotal; getData(&days, &airfare, &ground, &rate, &food, &enter); calctotal(days, airfare, ground, rate, food, enter, &totalF, &totalR, &total); output(days, airfare, ground, rate, food, enter, totalF, totalR, total); return 0; }