Answer:
A. the rise and fall of the tides.
C. a dropped object always falls toward Earth.
Explanation:
Gravity is considered to be a universal force of attraction which acts between all objects that has both mass, energy and occupy space. Therefore, it acts in such a way as to bring objects together.
Additionally, the gravity of earth makes it possible for all physical objects to possess weight.
The two phenomena which are evidence that gravitational forces are attractive includes;
I. The rise and fall of the tides: this is caused as a result of the gravitational force of attraction exerted by the moon on earth.
II. A dropped object always falls toward Earth: this acceleration is due to the gravitational force of attraction between the Earth and the object.
The better answer is organism
The variations might help the organism to survive if there is a change in its environment
Eg heat resistant bacteria
The variation might help the organism survive predators
Eg. Green beetles blend with green leaves thus disabling crows to spot them
:)
B) Native fish species will begin to decrease in population size.
A decrease in dissolved oxygen.
This is because oxygen is a byproduct of photosynthesis. If the plants are in water, some of the oxygen they produce will become dissolved in it. Without those plants, you have less dissolved oxygen.