$\backslash$table$[[$Less treasury stock, at cost:$,,],[741,052,632$ shares in current year and $649,576,808$ shares in prior year,$36,160,30,482],[$Total Merck & Co$.,$ Inc. stockholders' equity,$$48,480,$$$49,624$

ANSWER FOR b$,$ c$,$ AND d

$\backslash$table$[[$Merck & Co$.,$ Inc. Stockholders' Equity $($$ millions$),\backslash$table$[[$Current$],[$Year$]],\backslash$table$[[$Prior$],[$Year$]]],[$Common stock, $$0\mathrm{.}50$ par value,,$],[$Authorized$-6,500,000,000$ shares,,$],[$Issued$-3,688,014,021$ shares in current and prior year,$$1,844,$$$1,844$