Archimedes' principle states that a body immersed in a fluid is subjected to an upwards force equal to the weight of the displaced fluid. This is a first condition of equilibrium. We consider that the above force, called force of buoyancy, is located in the centre of the submerged hull that we call centre of buoyancy.
The answer is A. Hope this helps!!!
There are four quantum numbers:
1) Principal quantum number which tells the shell in which the electron is and is an integer number starting from 1. Both of these electrons are in the same shell, the third.
2) Azimuthal quantum number which tells the subshell of the electron. This has a value of an integer starting from 0, 0 being the s orbital. The first electron is in the d orbital due to the number being 2 and the second is in the p orbital due to the number being 1.
3) Magnetic quantum number tells the orbital within the subshell. The first electron is in the -1 orbital of the d subshell (which has values from -2 to 2) and the second is in the -1 orbital of the p subshell (which has values from -1 to 1).
4) Spin quantum number which specifies the spin on the electron, both of the electrons have the same spin.
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