Answer:
Chemical bonds
Explanation:
The chemical bonds hold the different type atoms or ions together.
The type of chemical bonds :
1. Ionic bond ;
Ions or atoms changes the electron and form ionic bond.Those atoms gains the electron gets negative charge and those atoms donate the electron gets positive charge.
2.Covalent bond :
In this type of bond atoms share the electrons and form covalent bonds.
3. Metallic bond :
This type of bond are present in the metals.In this atoms are used free electrons to form bonds.
Therefore answer is --
Chemical bonds
The correct answer is A. Acid rain forms from human activities and lowers the pH of rainwater below 7
Explanation:
The term "acid rain" is used to refer to rainwater with a low pH or a high acidity, this includes rainwater with a pH below 7 (solutions with a pH under 7 are acidic). In terms of formation, acid rain is mainly the result of human activities such as factories or cars that release pollutants into the atmosphere including nitric and sulfuric acids and these alter the natural pH of rain and makes it more acidic. Additionally, acid rain has negative consequences such as the death of fishes and other organisms in lakes, rivers, etc. because the acidity is toxic to many organisms. Thus, acid rain is the result of human activities and it lowers the pH of rain (Option A).
Answer: True.
Explanation:
A resistance force is also known as friction. And the efficiency of a machine is affected by friction.
A machine of lower efficiency has higher magnitude of friction than a machine of higher efficiency.
Therefore, To obtain the same resistance force, a greater force must be exerted in a machine of lower efficiency than in a machine of higher efficiency. This is true
The weather report never tells the "humidity" of the air. It tells the
"RELATIVE humidity". That's the percent of the moisture the air
COULD hold at the current temperature that it's actually holding
right now.
If the air is completely dry, then it's holding NONE of the moisture
that it COULD hold, and the relative humidity is zero percent.
I would say radio waves infared rays and xray
