Answer:
3. water
Explanation:
Specific Heat: Specific heat of a substance is the energy required to increase temperature of 1 gram of substance by 1°C
Here water has the highest specific heat in the list,so it emit largest amount of heat with lose of small amount of temperature.
So,water can warmed body until its temperature becomes below the body temperature.
The question is incorrect, nitration of methylbenzoate occurs at 3 position to get, methyl 3-nitrobenzoate.
This is because, in present reaction the reactant i.e. methylbenzoate, has low electron density at m-position.
Due to this, NO2+ prefentially attaches m-position to form methyl 3-nitro benzoate as the product.
A detailed reaction mechanism for formation of product is provided below.
Option B is correct. Average speed can be found through the equation speed = distance/time. Applying this to each person using the data in the chart:
Dennis’ speed: 60 ft/0.5 secs = 120 ft per sec
Johnny’s speed: 60 ft/0.45 secs = 133.333 ft per sec
Travis’ speed: 60 ft/0.52 secs = 115.38 ft per sec
Michael’s speed: 60 ft/0.48 secs = 125 ft per sec
As you can see, Johnny’s speed is the fastest at 133.333 ft/sec.
Answer : The metal used was iron (the specific heat capacity is
).
Explanation :
In this problem we assumed that heat given by the hot body is equal to the heat taken by the cold body.


where,
= specific heat of unknown metal = ?
= specific heat of water = 
= mass of unknown metal = 150 g
= mass of water = 200 g
= final temperature of water = 
= initial temperature of unknown metal = 
= initial temperature of water = 
Now put all the given values in the above formula, we get


Form the value of specific heat of unknown metal, we conclude that the metal used in this was iron (Fe).
Therefore, the metal used was iron (the specific heat capacity is
).