Agiant elliptical can contain of stars.

Trillions

Explanation:

Giant ellipticals are galaxies that are built by the collisions of many smaller galaxies. This creates massive groups of trillions of stars. Elliptical galaxies do not have a clear structure, and thus come in many shapes and sizes. Moreover, the stars that make up giant ellipticals are among the oldest in the universe.

italian workers migrated to northern provinces

b.

developed countries have tended to improve the environment, while developing countries have tended to damage it.