answer: focus or hypocenter
 
enplanation: when energy release at the focus, seismic waves travel outward from that point in all directions. 
 
        
             
        
        
        
Explanation:
(1).   It is known that in a reaction equation, reactants are placed or written on left hand side and products are written on the right hand side. 
For example, 
Hence, in a reaction equation you start with the reactants and end up with the products.
(2).   The number of atoms in a reaction will remain the same because according to the law of conservation of mass, mass of reactants will be equal to the mass of products.
Therefore, number of atoms on the reactant side will be equal to the number of atoms on product side.
 
        
             
        
        
        
From the calculations, the half life of the material is 6.5 days.
<h3>What is radioactivity?</h3>
The term radioactivity has to do with the spontaneous disintegration of a specie.
Uisng the formula;
N=Noe^-kt
N= amount at time t = 0.135 Ci or 4.995 ×10^9 Bq
No = amount initially present =  1.75 x 10^12 Bq 
k = rate constant = ?
t = time taken = 55 days
Hence;
4.995 ×10^9  = 1.75 x 10^12e^-55k
4.995 ×10^9/1.75 x 10^12 = e^-55k
2.85 * 10^-3 = e^-55k
ln2.85 * 10^-3 = -55k
k = ln2.85 * 10^-3/-55
k = 0.1066 day-1
Half life = 0.693/ 0.1066 day-1
= 6.5 days
Learn more about radioactivity:brainly.com/question/1770619
#SPJ1
 
        
             
        
        
        
Answer:
1.181 × 10²⁴ molecules CO₂
General Formulas and Concepts:
<u>Chemistry - Atomic Structure</u>
- Reading a Periodic Table
- Using Dimensional Analysis
- Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.
Explanation:
<u>Step 1: Define</u>
86.34 g CO₂
<u>Step 2: Identify Conversion</u>
Avogadro's Number
Molar Mass of C - 12.01 g/mol
Molar Mass of O - 16.00 g/mol
Molar Mass of CO₂ - 12.01 + 2(16.00) = 44.01 g/mol
<u>Step 3: Convert</u>
<u /> = 1.18141 × 10²⁴ molecules CO₂
 = 1.18141 × 10²⁴ molecules CO₂
<u>Step 4: Check</u>
<em>We are given 4 sig figs. Follow sig fig rules and round.</em>
1.18141 × 10²⁴ molecules CO₂ ≈ 1.181 × 10²⁴ molecules CO₂