Final Answer is - 197.53948
Im not 100% on these but i can try
1. A compound is made up of elements and their different atoms
2.
A. salt- compound (NaCl) is two elements Na (sodium) and Cl (chloride?)
B. Nitrogen- element its on the periodic table
C. Helium- element its on the periodic table
D. Water- compound (H2O) two elements hydrogen and oxygen
3. element, compound, compound, element
Hope this helps
r₁ = distance of the point from the source = 43 km = 43000 m
I₁ = intensity of earthquake wave at distance "r₁" = 2.5 x 10⁶ W/m²
r₂ = distance of the point from the source = 1.5 km = 1500 m
I₂ = intensity of earthquake wave at distance "r₂" = ?
we know that , for a constant power , the intensity of wave is inversely proportional to the distance from the source .
I α 1/r² where I = intensity of wave , r = distance from source
hence we can write
I₁/I₂ = r₂²/r₁²
inserting the values
(2.5 x 10⁶) /I₂ = (1500/43000)²
I₂ = 2.1 x 10⁹ W/m²