Which command or key combination allows a user to return to the previous level in the command hierarchy?

Which type of file can be used to import data into a spreadsheet?

How is the brightness of oled of the diaplay is controled

4. what is the reason for including the following code snippet in the header file animal. h? #ifndef animal_h #define animal_h class animal { public: animal(); animal(double new_area_hunt); void birth(); void hunt(double new_area_hunt); void death(); double get_area_hunt() const; private: double area_hunt; }; #endif