please help me by showing me to make unit test

Given the following class, write a unit test in the MovieSuite test suite for the add_rating (double) function. The add_rating (double) function adds a rating value to the rating member variable and increments the rating_count . Use the Google Test framework. You can assume that all other functions in the class are fully tested. class Movie { private: string title; double rating; int rating_count; public: Movie (string title); //sets title and initializes rating and rating_count to zero string get_title () ; double get_average_rating () ; //returns average rating (i.e. , rating / rating_count) void add rating (double) ; /* Your Unit Test Should Go Below */ Enter your answer here