Tides are affected by
a) earth's gravity alone.
b) the moon's gravity alone.
c) the sun's gravity alone.
d) the gravity of the moon and the sun.

The moons gravity because the tides change throught the day as it becomes night

Humans have survived and thrived in mexico city by using technology to create greater access to land. when the spanish conquered the aztec capital, tenochtitlan, in the 16th century, they built mexico city by draining the lakes and filling in the lake water to create more arable land for agriculture. this technique of land reclamation has continued to be fundamental to human civilization in mexico city.