hydrogen is the lightest element in the periodic table
I would say D, because you need to start with nothing to measure the different sizes as they start to grow. hope this helps!
Answer: I think they form on the Hawaiian islands because of the volcano.
Explanation: The heat may help them form,hope this helps.
Answer: the top one is 5.3 s and the bottom one is tenths of seconds
Explanation:
Note that
The heating value of standard coal is about 30,080 kJ/kg
1 L of water has a mass of 1.0 kg
The mass of 15 L of water = 15 kg.
The latent heat of vaporization of water is about 2260 kJ/kg,
The energy required to boil 15 L of water is
(2260 kJ/kg)*(15 kg) = 33900 kJ
The mass of coal required to provide this energy is
(33900 kJ)/(30080 kJ/kg) = 1.127 kg
Because 1 kg = 2.205 lb, the mass of coal required is
(1.127 kg)*(2.205 lb/kg) = 2.485 lb
Answer: 2.49 lb (nearest hundredth)