i need how my professor found these answers. i need explanation please.

question : Chapter 11 Practice: Shell Oil Corp has 2 classes of stock: Common $5 par, 1,700,000 shares; Preferred $10 par, 5% cumulative and non-participating, 1,000,000 shares.

Record the issuance of this stock as of January 1^st, 2021 assuming the common was issued for $8 per share and the preferred was issued at par.

answer :

Date	Account	Debit	Credit
1/1/2021	Cash (1,700,000 x $8)	$13,600,000
	Common Stock		$8,500,000
	Paid in Capital in Excess of par		5,100,000
1/1/2021	Cash	$10,000,000
	Preferred Stock		$10,000,000

question :

On December 1^st, 2022, the Preferred shares currently have $200,000 of dividends in arrears due to a short payment from the prior year. On December 10^th, 2022, Baker Hughes announces a $900,000 dividend to be paid to the shareholders as of the record date December 15^th. The payment will be made December 31^st.

Record all of the dividend journal entries for this situation.

answer :

Date	Account	Debit	Credit
12/10/2022	Dividends	$900,000
	Dividends Payable Common		$200,000
	Dividends Payable - Preferred		700,000
12/31/2022	Dividends Payable Common	$200,000
	Dividends Payable - Preferred	700,000
	Cash		$900,000