Name a modern convenience that was invented when Verdi was over 60 years old

The diagram shows the positions of the sun, moon and earth during spring tides, when the high tides are at their highest and low tides at their lowest. what is it about these positions that causes these high and low tides?

Rocks that contain crystals that are roughly equal in size and can be identified with the unaided eye are said to exhibit a texture.

In the figure, polygon abcd is transformed to create polygon a′b′c′d′. this transformation is a by a factor of .