Explanation:
Given that,
Rate of cooling of air
Initial temperature= 80°C
Final temperature = 5°C
We need to calculate
Using newton's law of cooling


Where, 
Here,
= 25°C (surrounding temperature)
dt = 1 minute

Put the value into the formula



Hence, This is the required answer.
Answer:
B. The atom gains 1 electron, to make a total of 18 electrons.
Explanation:
Chlorine is the 17th element in the periodic table, so it has atomic number 17:
Z = 17
This means that a neutral atom of chlorine has 17 protons and 17 electrons.
When a chlorine atom gains 1 electron, its electric charge (initially zero) becomes -1, since the electron has negative charge of -1 (in elemntary charge units). This also means that the number of electrons in the ion is now
17 + 1 = 18
So the correct answer is
B. The atom gains 1 electron, to make a total of 18 electrons
<span>principal quantum number (n) </span>represents the relative overall energy of each orbital
Hope this helps!
To solve this problem it is necessary to apply the concepts related to the Period based on the length of its rope and gravity, mathematically it can be expressed as

g = Gravity
L = Length
T = Period
Re-arrange to find the gravity we have

Our values are given as

Replacing we have



Therefore the correct answer is C.