A is the correct answer !!!
Answer:
The answer to your question is 636.6 ft
Explanation:
Data
base = 425 ft
angle = 39°
See the picture below
1.- Divide the triangle to get two right triangles.
Now the superior angle will measure 19.5° and the opposite side will measure 212.5 ft
2.- Use the trigonometric function sine to find the hypotenuse
sin 19.5 = 212.5/hyp
solve for hyp
hyp = 212.5 / sin 19.5
Result
hyp = 212.5/ 0.333
hyp = 636.6 ft
Answer:
See below explanation
Explanation:
The correspondent chemical reaction for copper carbonate decomposed by heat is:
CuCO₃ (s) → CuO (s) + CO₂ (g)
Considering all molar mass (MM) for each element ( we consider rounded numbers) :
MM CuCO₃ = 123 g/mol
MM CuO = 79 g/mol
MM CO₂ = 44 g/mol
Statement mentions that scientis heated 123.6 g of CuCO₃ (almost a MM), until a black residue is obtained, which weights 79.6 g : this solid residue is formed by CuO, and the remaining mass (approximatelly 44 g) belongs to teh second product, this is, CO₂; as it is a gas compund, it is not certainly included on the solid residue.
So, law of conservation mass is true for this case, since: 123.6 g = 79.6 g + 44 g. As explained, on the solid residue, we don not include the 44 g, which "escaped" from our system, since it is a gas compound (CO₂)
