C. 50%
Unless the question is saying he only gets heads once, in which case it would be 0%. Or the coin could have 2 heads. Then it would be 100%.
But I'm pretty sure it's 50%.
Answer:
Since the noble gases are unreactive or inert, they are safe to use. Helium is used to fill balloons and airships, because it is much lighter that air and it will not catch fire. Neon is used in advertising signs. It will give red glow, but the color can be changes by mixing it with other gases.
Explanation:
The answer is 290.66 mL
Explanation:
The density of any substance including styrofoam is determined by two main factors: mass (atoms in the substance) and volume (space occupied). Moreover, the volume or mass of the substance can be calculated by using the density as these variables are related. Below I show the process:
density = mass / volume
mass = density x volume
volume = mass / density
volume = 21.80 g / 0.075 g/mL
volume = 290.66 mL
The Law of Conservation of Mass<span> states that </span>matter <span>can neither be created nor destroyed in a chemical reaction.</span>
1500 cm^3 ; 1 mL equals 1 cm^3
