No.
Yes, they are. All custom made calendars will be unique since not everyone is the same. No person will have the exact same thing as another person since not everyone has the exact same personal preference.
they are the same exact size
The acceleration due to gravity is the same for all objects because it depends only on the mass of the Earth and the distance from its center, and not on the objects' mass or composition. This means that all objects, regardless of their size or weight, fall towards the Earth at the same rate of 9.8 m/s^2 (on the surface of the Earth).
So that everyone knows that they are talking about the same thing, and to organize the information and objects.
Because the force of gravity exerting on objects on the moon is much lower than that of the earth.
The gravitational acceleration of an object near Earth is the same because it depends only on the mass of the Earth and the distance from the center of the Earth. This means that all objects experience the same gravitational acceleration, regardless of their mass or composition.
No, just as in a solar eclipse, the sun, earth and moon are in different positions depending on where you are on the earth. If we could all see it at the same time that would mean we would all be in the same exact spot on the earth.
No, some words are different in Spain then the Americas.
Yes. Everyone on earth for whom the moon is visible sees the same phase at the same time.
Objects are congruent if they are the same size and shape, or an exact reflection of one another. If objects are not congruent, they are dissimilar in either size, shape or both.
Gravity causes all objects to fall to earth at the same time. (some objects do not like paper and yarn because of air resistance. but if you block the air resistance by placing it on a book and dropping, it will fall at the same time. Or if you reduce surface area) Gravity causes all objects to fall with an acceleration of 9.8m/s*2
Yes. Neglecting the effects of air resistance, ALL objects fall with the same acceleration near the surface of the earth, meaning that any two objects dropped at the same time will have the same velocity after the same time interval.