7 A spherical snowball originally has a radius of 8 cm As it

7. A spherical snowball originally has a radius of 8 cm. As it melts, the radius decreases at a rate of 0.6 cm./minute. Which of the following defines the volume of the snowball (in cm3) as a function of the number of minutes since the snowball began melting? The volume of a sphere of radius r is given by the formula V) (a) g(t) 8-0.6t (c) g(t)(8 0.6t3) (d) g(t)8 0.6t)

Solution

Volume of a sphere is (4/3)*?*(r^3)

After 1 min - Radius reduces by 0.6

After 2 min - Radius reduces by 1.2 or 0.6*2

After 3 min - Radius reduces by 1.8 or 0.6*3

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After \'t\' min - Radius reduces by 0.6*t

Then the volume of the ball is given by

g(t) = (4/3) * ? * ((8 - 0.6t)^3) - Option D