The heat absorbed is calculated using the following equation:
Q = mCΔT
Q = heat absorbed
m = mass = 66 g
C = specific heat of iron = 0.449 J/g.°C
ΔT = temperature change = 20 - 7 =13°C
Therefore,
Q = 66*0.449*13 = 385.242 J
When a spoon is in a cup of water, is called refraction.
Answer:
a)The approximate radius of the nucleus of this atom is 4.656 fermi.
b) The electrostatic force of repulsion between two protons on opposite sides of the diameter of the nucleus is 2.6527
Explanation:

= Constant for all nuclei
r = Radius of the nucleus
A = Number of nucleons
a) Given atomic number of an element = 25
Atomic mass or nucleon number = 52


The approximate radius of the nucleus of this atom is 4.656 fermi.
b) 
k=
= Coulombs constant
= charges kept at distance 'a' from each other
F = electrostatic force between charges


Force of repulsion between two protons on opposite sides of the diameter



The electrostatic force of repulsion between two protons on opposite sides of the diameter of the nucleus is 2.6527
Answer:
Option 2 - Standard deviation
Explanation:
To find : Which measure of dispersion indicates the extent to which each individual score in a data set varies from the mean of that set?
Solution :
Standard deviation is defined as,
- It is a mathematical measure that is used to evaluate the difference between the mean value of a set of number and each value in the group.
- It is calculated as the square root of variance by determining the variation between each data point relative to the mean.
The measure of dispersion that indicates how much scores in a sample vary around the mean of the sample is the standard deviation.
Therefore, option 2 is correct.