Question

একটি ঘনকের একটি তলের পরিসীমা 12 মিটার হলে এর আয়তন কত ​

Answer 1

Answer:

could uhh plz translate in English

Step-by-step explanation:

The number of protons is the atomic number, and the number of protons plus neutrons is the atomic mass. For hydrogen, the atomic mass is 1 because there is one proton and no neutrons. For helium, it is 4: two protons and two neutrons.

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2.1 Electrons, Protons, Neutrons, and Atoms.

Element .

Symbol .

Atomic No. .

Number of Electrons in Each Shell First .

Second .