Start with this code and fill in the functions ############################################################################################################################## #include #include #include...

#include
#include
#include
#include
using namespace std;
class River
{
string name;
double kmLength;
public:
River() :
River("", -1) {
}
River(string name, double kmLength) {
this->name = name;
this->kmLength = kmLength;
}
double getKMLength() const {
return kmLength;
}
void setKMLength(double kmLength) {
this->kmLength = kmLength;
}
const string& getName() const {
return name;
}
void setName(const string &name) {
this->name =...