Answer:
0.75 grams
Explanation:
Today we have 6 grams
In 30 years, 3 grams remain
In 60 years 1.5 grams remain
in 90 years 0.75 grams remain
mathematically It would look like this
m = 6(0.5⁽ⁿ/³⁰⁾) where n is number of years
Solar roller is a cool name
Answer: 
Explanation:
The quantity of heat required to raise the temperature of a substance by one degree Celsius is called the specific heat capacity.

Q = Heat absorbed= 16.7 kJ = 16700 J (1kJ=1000J)
m= mass of benzene = 225 g
c = specific heat capacity = 1.74 J/gK
Initial temperature of the water =
= 20.0°C = 293 k 
Final temperature of the water =
= ?
Change in temperature ,
Putting in the values, we get:


The final temperature will be 