Adding a note to a melody or spontaneously making up a melody on the spot it's called

It is called improvisation.

it's a secular holiday. it is and was a custom developed to recognize the ending of a time and a wish for a good future. the kind of kiss you exchange, if you are single, is intended to predict what kind of year you will have in the coming year.

it is saying good bye to the last year with all its ups and downs, and hello to the new year, with all its hopes and dreams.

the phenomenon that would be cited as evidence of increased economic interdependence between europe and the americas is  the development of mercantilism.

this theory suggests that the wealth of a country depends on its economic assets, or capital.

hope this : )