Answer:
D
really dude, just read these types of questions the one that's really different is usually right
Explanation:
Determining a substance's physical or chemical identity. What are the two main requirements for identification? The adoption of testing procedures that give characteristic results for specific standard materials and the number and type of tests needed to identify a substance to exclude all other substances.
Valence electrons are the electron on the outer energy level and they are important because they tell if that element is compatable
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.