After 3 half life periods you would have 5 grams of krypton left because half of 40 is 20 half of 20 is 10 and half of 10 is 5
Answer:
f = frequency = 590,000 Hz ===> 59×10^4 Hz
λ = Wavelength = ?
c = Speed of light in a vacuum = 3 × 10^8 m/s
** Hz = 1/sec
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I hope I helped you^_^
L'air n'est pas un mélange gazeux, donc la réponse serait le verre
My cereal box says "net wait g (500)" so it's probably Grams