question 1.

#include <iostream>

using namespace std;
//Abstract class becuase it contain ppure virtual function
class Vehicle{
    
    public:
   virtual void drive() = 0;
};

class Car: public Vehicle{
    public:
    void drive(){
        cout<<"Driving a car "<<endl;
    }
};

class Motorcycle: public Vehicle{
    public:
    void drive(){
        cout<<"Driving a motorcycle"<<endl;
    }
};


int main() {
    //Abstract class can not be instantiated. but you can write as pointer and 
    Vehicle *obj;
   Car c;
   obj = &c;
   obj->drive();
   Motorcycle m;
   obj = &m;
   obj->drive();

    return 0;
}
//OUTPUT:
Driving a car 
Driving a motorcycle
____________________________________________________________

Question 2:
#include <iostream>

using namespace std;

class Shape{
    
    public:
   double Area(){
       return 0.0;
   }
   
};

class Rectangle: public Shape{
    double width;
    double length;
    public:
    Rectangle(double width, double length){
        this->width = 10;
        this->length = 10;
    }
    double Area(){
        //int area = width * length;
        return width * length;
        //cout<<"Area of Rectangle = "<<area<<endl;
    }
    
};

class Triangle: public Shape{
    double base;
    double heigth;
    public:
    Triangle(double b, double h):base(b),heigth(h){
        
    }
    double Area(){
        return 0.5 * base * heigth;
    }
};

int main() {
    Shape *shape;
    Rectangle rect(10, 10);
    shape = &rect;
    shape->Area();
   
    

    return 0;
}

________________________________________________________________-
  Question 3.
#include <iostream>

using namespace std;

class Animal{
    
    protected:
    string name;
    public:
    Animal(string name){
        this->name = name;
    }
    virtual void makeSound(){
        cout<<"Animal: "<<endl;
    }
   
};

class Dog: public Animal{
    string breed;
    public:
    Dog(string name, string breed):Animal(name){
        this->breed = breed;
    }
    void makeSound(){
        //Animal::makeSound(); to call makeSound function in Animal class
        cout<<"Dog makes Sound."<<endl;
    }
    void display(){
        cout<<"Dog Name: "<<name<<endl;
        cout<<"Dog Breed: "<<breed<<endl;
    }
};

class Cat: public Animal{
    string color;
    
    public:
    Cat(string name, string color):Animal(name){
        this->color = color;
    }
    void makeSound(){
        cout<<"Cat makes Sound."<<endl;
    }
    void display(){
        cout<<"Cat Name: "<<name<<endl;
        cout<<"Cat Color "<<color<<endl;
    }
};

int main() {
    
    
    Dog d("Doggy","Male");
    d.display();
    d.makeSound();
    cout<<endl;
    Cat c("Catty","Brown");
    c.display();
    c.makeSound();
   
    

    return 0;
}
//OUTPUT:
Dog Name: Doggy
Dog Breed: Male
Dog makes Sound.

Cat Name: Catty
Cat Color Brown
Cat makes Sound.