The answer is b. radon-222. The alpha decay means that it will emit an alpha particle when decays. The alpha particle has two protons and two neutrons. So Radium(88) minus two protons will become Radon(86). And the atomic mass will become 226-4=222.
2mm=2,000,000 nm
2,000,000/25=80,000
The answer is 80,000 polio viruses
Answer: Scientific reasoning
Explanation:
A scientific reasoning can be defined as the justification which connects the evidence with that of the claim and it rules out all those claims that are not supported by any evidence. It explains the fact that how evidence can support a claim and scientifically acceptable conclusion can be drawn. An argument is always based on one or more claims which can either be true or evidentially proved.
Answer:
a) V air/day = 8640 L air an adult breaths / day
b) 0.0181 L CO intake a person / day
Explanation:
a) one average person has 12 breaths for min:
in each breath it take an average of 500 mL on air.
⇒ 12 breath / min * 500mL air / breath = 6000 mL air / min
the average air volume per day of a person is:
⇒ Vair/day = 6000 mL air / min * (60 min / h) * ( 24 h / day ) = 8640000 mLair / day * ( L / 1000 mL)
⇒ V air / day = 8640 L / day
b) 2.1 E-6 L CO / L air * 8640 L air / day = 0.0181 L CO / day
Given the mass of 
=25.6 g
The molar mass of =390.35g/mol
Converting mass of to moles:
Converting mol to mol S:
Converting mol S to atoms of S using Avogadro's number:
1 mol = 
