maths question?

Question

In madras, temperature at noon varies according to t^2/3 + 4t + 12, where t is elapsed time. Find how much tem more or less in 6 pm to 8 pm.(not exactly 6 and 9 but other values are given.. remember " -" sign was not there before t)

Answer 1

Hint:

f(t)=t^2/3 + 4t + 12

for t=12 then 12^2/3 + 4*12 + 12=48+48+12=108