A statement would be to the effect that plants use oxygen as part of photosynthesis
I think the correct answer would be that there are a relatively small number of moles of HCl present. Dilute would mean that there are very few solute particles dissolved as compared to the solvent particles in the solution. Hope this helps.
What that means is the atom is so radioactive that the nucleus is unstable.
1,000 W = 1 kW
100 W = 0.1 kW
(0.1 kW) x (6 h) = 0.6 kWh <=== energy
(0.6 kWh) x (£0.1359/kWh) = £0.0815 <=== cost of it
