Question

to which period A and B belongs to? in periodic table lesson​

Answer 1

Answer:

Calcium (Ca) is in group 2, for it contains two valence electrons. In the old IUPAC system the letters A and B were designated to the left (A) and right (B) part of the table, while in the CAS system the letters A and B are designated to main group elements (A) and transition elements (B).

Answer 2

${\large\blue{\mathbb\fcolorbox{aqua}{darkblue}{● QUESTION:}}}$

❥︎ ❥︎ ᴊᴏᴜʀɴᴀʟ ᴇɴᴛʀʏ ғᴏʀ ᴘᴀɪᴅ 250 ᴛᴏᴡᴀʀᴅs ᴘᴏsᴛᴀɢᴇ ᴇxᴘᴇɴsᴇs.

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${\large\blue{\mathbb\fcolorbox{aqua}{darkblue}{● ANSWER:}}}$

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➪ ᴘᴏsᴛᴀɢᴇ ᴇxᴘᴇɴsᴇs ᴀ/ᴄ ... ᴅʀ. 250

ᴛᴏ ᴄᴀsʜ ᴀ/ᴄ ... ᴄʀ. 250

(ʙᴇɪɴɢ ᴀᴍᴏᴜɴᴛ ᴘᴀɪᴅ ғᴏʀ ᴘᴏsᴛᴀɢᴇ ᴇxᴘᴇɴsᴇs)

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${\large\bold\orange{》 ❥︎ \:ꀍꂦᖘꏂ \: ꓄ꀍꀤꌚ \: ꀍꏂ꒒ᖘꌚ \: ꌩꂦꀎ \:♡︎ 《}}$

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