Answer:
The mass is 
Explanation:
From the question we are told that
The initial temperature is 
The final temperature is 
Generally the maximum heat produced by 1 Liter of natural gas is
So the amount of heat produced by 100 L is

=> 
Generally given that the efficiency is 
Then actual heat received by the water is

=> 
=>
Converting to kcal
=> 
Generally the specific heat of water is

Generally the heat received by the water is mathematically represented as

=> 
=> 
Answer:
(D) parasite........................
B. carbon + oxygen -- carbon dioxide
Explanation:
The best equation that describes a reaction where carbon combines by burning in the presence of oxygen to produce carbon dioxide is:
carbon + oxygen -- carbon dioxide
Every chemical reaction is made up of reactants and products
Reactants are the species on the left hand side of an equation, the products are those on the right hand side.
The reactants combines chemically to give produces.
The kind of reaction depicted above is a synthesis or combination reaction where two species combines to gives a product or more;
C + O₂ → CO₂
learn more:
Chemical reaction brainly.com/question/3953793
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