P=m/V
m=40.24 g
V=50.0 mL=50.0 cm³
p=40.24/50.0=0.8048 g/cm³
It's been a while since I've done this stuff... I'm pretty confident 3. is decibels. 2 could be perception (because perception is the pitch that a human hear designates to the frequency it receives). I'm unsure about the first one.
207 is the mass number. 82 would be the atomic number
<span>Incomplete combustion will occur when there is not enough oxygen to allow the fuel to react completely to produce carbon dioxide and water. It also happens when the combustion is quenched by a heat sink, such as a solid surface or flame trap.
The answer is C. Carbon dioxide.
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Metamorphic rock. This is because when heat is projected onto these rocks, they morph into different metamorphic rocks.