The following diagram shows the path of a planet around the Sun. Kepler discovered that _. area A = area D
the distance from P 1 to P 2 equals the distance from P 3 to P 4
area A = area C
the speed in the interval from P 1 to P 2 equals the speed in the interval from P 3 to P 4

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The problem here is that according to aufbau principle before 3d orbital 4s subshell comes.after filling 3p orbital with electrons you have 4 electrons left, you place two in 4s with opposite spin and the other two in 3d in any of its two orbitals of total five orbitals with the same spin.