Answer:
Jeweler B = more accurate 
Jeweler A = more precise 
Error:
0.008, 0
% error :
0.934% ; 0
Explanation:
Given that:
True mass of nugget = 0.856
Jeweler A: 0.863 g, 0.869 g, 0.859 g
Jeweler B: 0.875 g, 0.834 g, 0.858 g
Official measurement (A) = 0.863 + 0.869 + 0.859 = 2.591 / 3 = 0.864
Official measurement (B) = 0.875 + 0.834 + 0.858 = 2.567 / 3 = 0.8556
Accuracy = closeness of a measurement to the true value
Accuracy = true value - official measurement 
Jeweler A's accuracy :
0.856 - 0.864 = - 0.008
Jeweler B's accuracy :
0.856 - 0.856 = 0.00
Therefore, Jeweler B's official measurement is more accurate as it is more close to the true value of the gold nugget. 
However, Jeweler A's official measurement is more precise as each Jeweler A's measurement are closer to one another than Jeweler B's measurement which are more spread out. 
Error:
Jeweler A's error :
0.864 - 0.856 = 0.008
% error =( error / true value) × 100
% error = (0.008/0.856) × 100% = 0.934%
Jeweler B's error :
0.856 - 0.856 = 0 ( since the official measurement as been rounded to match the decimal representation of the true value) 
% error = 0%
 
        
             
        
        
        
Answer:
There is 17.1 kJ energy required 
Explanation:
Step 1: Data given
Mass of ethanol = 322.0 grams
Initial temperature = -2.2 °C = 273.15 -2.2 = 270.95K
Final temperature = 19.6 °C = 273.15 + 19.6 = 292.75 K
Specific heat capacity = 2.44 J/g*K
Step 2: Calculate energy
Q = m*c*ΔT
 ⇒ m = the mass of ethanol= 322 grams 
 ⇒ c = the specific heat capacity of ethanol = 2.44 J/g*K
 ⇒ ΔT = T2 - T1 = 292.75 - 270.95 = 21.8 K
Q = 322 * 2.44 * 21.8 = 17127.8 J = 17.1 kJ
There is 17.1 kJ energy required 
 
        
             
        
        
        
B............................................................................
        
             
        
        
        
Answer:co2 
Explanation:because of the oxygen levels