Answer: C. Metals tend to easily lose their valence electrons.
Explanation:
Metals are those substances which have tendency to loose their valence electrons to attain noble gas configuration and forms positive ions called as cations.
Example: Gold, potassium etc

Non metals are those substances which have tendency to gain valence electrons to attain noble gas configuration and form negative ions called as anions.
Example: Sulphur, Chlorine

Answer:
C
Explanation:
Answer: C. A thoroughly tested and widely accepted explanation. Explanation: A scientific theory is a coherent statement or set of ideas that explains observed facts or phenomenon and are thoroughly tested and widely accepted.
The Answer is A. Mirrors.
This is because a mirror has a sheet of metal behind the glass, perhaps silver, that reflects the light back, making an image.
Answer:
744.9 mmHg ≅ 745 mmHg
Explanation:
The base to solve this, is the Ideal Gases Law. The mentioned formula is:
P . V = n . R . T
To compare two situations, we can propose:
For the first situation P₁ . V₁ = n₁. R . T₁
For the second situation P₂ . V₂ = n₂ . R . T₂
As the sample has the same moles and R is a constant value, we can avoid them so: (P₁ . V₁) / T₁ = (P₂ . V₂) / T₂
We need to make Tº unit conversion:
25ºC + 273 = 298K
We replace data → (370 mL . 1020 mmHg) / 298K = (P . 510 mL) / 300 K
(377400 mL.mmHg / 298K) . 300 K = P . 510 mL
379932.8 mL . mmHg = P . 510 mL
(379932.8 mL . mmHg) / 510 mL = P → 744.9 mmHg
Answer:
true, they both have different types of DNA.