Hey there!:
Here the Statement - D is correct.
Because Orbitals containing the core electrons are more attracted towards nuclear charge and hence less shilded from nuclear charge than an orbital that doesn't penetrate. Also due to more attraction between the orbital containing core electron and nucleus, it will have less energy.
Hope this helps!
Answer:
The mass of the massive object at the center of the Milky Way galaxy is 
Explanation:
Given that,
Diameter = 10 light year
Orbital speed = 180 km/s
Suppose determine the mass of the massive object at the center of the Milky Way galaxy.
Take the distance of one light year to be 9.461×10¹⁵ m. I was able to get this it is 4.26×10³⁷ kg.
We need to calculate the radius of the orbit
Using formula of radius



We need to calculate the mass of the massive object at the center of the Milky Way galaxy
Using formula of mass

Put the value into the formula


Hence, The mass of the massive object at the center of the Milky Way galaxy is 
Radio waves are the longest
To solve this problem we will apply the normal distribution, with which we will obtain the probability that the given event will occur. Concepts such as the mean and standard deviation will be present throughout the solution of the problem. Increasing or decreasing the average would change the location or center point of the curve. The change in the standard deviation would lead to the change in the dispersion of the data. As the standard deviation increases, the curve would become flatter.
Let X be the output voltage of power supply
X∼N 
A
The lower and upper specifications for voltage are 4.95 V and 5.05 V, respectively





Hence probability that a power supply selected at random will conform to the specifications on voltage is 0.9876