<span>A. Missing part is ⁴He₂
You can also calculate it by adding/subtracting for atomic mass & atomic numbers
Hope this helps!
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The answer is a. <span>changes in nucleotides of a DNA molecule that affect the genetic message.</span>
Hi there!
• Avogadro's number = 6.023 × 10²³
• No.of molecules in N = 1.806 × 10²² [ Given ]
It's known that :-
Number of molecules = Moles × Avogadro's number
=> 1.806 × 10²² = Mol. × 6.023 × 10²³
=> Mole =

=> Moles = 0.03 mol.
Hence, 0.03 mol. is th' required answer.
~ Hope it helps!