Answer:
1. A.
2.D.
3.B.
Explanation:
Notepad:
A. The present is key to the past. The geological processes ocurring today have always ocurred in the past. So if we want to predict what is going to happen in the future, we need to understand the Earth's past.
B. The tests that are used to determine when continental crust was formed are the relative dating and carbon prototyping
C. Open pit mining, this type of mining is very damaging to the environment because strategic minerals are often only available in small concentrations, which increases the amount of ore needed to be mined.
Endocrine gland - a group of cells that secretes substances into the blood or directly into an organ.
Differ from exocrine glands, endocrine glands have no ducts and secrete products (hormones) directly into blood.
Hormone - a substance produced by cells that helps specific groups of cells to perform specific functions. It is a product of endocrine gland which functions as chemical messengers to stimulate other cells.
Duct – a channel or tube that conveys a substance. It is part of the exocrine glands (such as salivary glands) which makes contact with surface .
Answer:
The correct answer is A. 3O₂ + 2Al → 2AlO₃
Law of conservation of mass states that mass can nether be created nor destroyed in a closed system or chemical reaction i.e. the total mass of the matter always remains the same throughout the chemical or physical change.
For example, in the given reaction 3O₂ + 2Al → 2AlO₃ the total mass of the reactants is equal to the total mass of the product.
Mass of oxygen = 16 x 3 = 48 AMU
Mass of aluminium = 2 x 27 = 54 AMU
Total molecular mass of the reactants = 102 AMU
Total molecular mass of the product = 2 x 27 + 6 x 8 = 102 AMU.
Hence, the total mass of the matter remains the same.
The answer is C.)sending them on the shuttle to be suspended in space. This is the answer because after the nuclear fuel rods come out of the reactor, they go into a deep pool to cool off. Then they are then stored in concrete and lead-lined casks for dry storage, until, ultimately, the US government builds a deep underground storage facility to house them permanently. They are never sent on the shuttle to be suspended in space<span>. It would be too costly and too dangerous.</span>
Answer:
Executive
Explanation:
having the power to put plans, actions, or laws into effect.