Answer:
A
Explanation:
To label an element correctly using a combination of the symbol, mass number and atomic number furnishes some important information about the element.
We can obtain these information from the element provided that correct labeling of the element is presented. Firstly, after writing the symbol of the element, the atomic number is placed as a subscript on the left while the mass number of the atomic mass is placed as a superscript on the same left.
Looking at the question asked, we have the element symbol in the correct position as Ca, with 42 also in the correct position which is the mass number. The third number which is 20 is thus the atomic number of the element.
I would say physical, because a physical change is affecting the form of a chemical substance, but not it's chemical makeup.
Answer:
Explanation:
Velocity is a physical quantity that expresses the relationship between the space traveled by an object, the time taken for it and its direction. In other words, velocity is associated with the change of position of a body over time.
Its unit in the International System of Units is the meter per second (
), but it can also be expressed in 
So, in this case, the speed on the way to work will be:
velocity= 36
The velocity on the way back home will be:
velocity= 27
Answer:
Nonmetals and nonmetals tend to form covalent bonds.
or
P and S
Explanation:
