Answer:
Impurities will be trapped in the crystals of the benzoic acid crystallized in this manner.
Explanation:
After benzoic acid is dissolved in hot water, it should have been allowed to cool gradually before it is transferred into an ice bath.
This gradual cooling will aid the separation of impurities so that when the vessel is now submerged in an ice bath, only pure benzoic acid is recrystalized.
If the vessel is immediately submerged into an ice bath, impurities will be trapped in the crystals of the benzoic acid.
Answer : The correct option is, 
Explanation :
The conversion used for the temperature from Fahrenheit to degree Celsius is:

where,
= temperature in Fahrenheit
= temperature in centigrade
The conversion used for the temperature from degree Celsius to Kelvin is:

where,
= temperature in Kelvin
= temperature in centigrade
As we are given the temperature in Fahrenheit is, -10
Now we have to determine the temperature in degree Celsius.



Now we have to determine the temperature in Kelvin.



Therefore, the temperature in degree Celsius and Kelvin are, 
Answer:
One
Explanation:
Trailing zeros in a number are not significant unless they follow a decimal point.
If you want to specify a different number of significant figures, you can use a decimal point.
For example,
2.0 × 10³ = two significant figures
2.00 × 10³ = three significant figures
2.000 × 10³ = four significant figure
2000. = four significant figures