Hi everyone, thanks for taking the time to help me out!

Question: An object of temperature 120 degree F is placed in a medium maintained at a constant temperature m degree F. At the end of 2 minutes the temperature of the object is 90 degree F and after another 2 minutes its temperature is 72 degree F.

(i) Find m

(ii) When will the temperature of the object be 61.20 degree F?

(iii) What is the temperature of the object at the end of 8 minutes?

(i) T(t)=Ta+(To-Ta)e^-kt

I know that Ta=90 F, To can be 120 degree F when T(2)=90 and t=2. I still have two unknowns left and i cant solve for Ta, so i need help here.

T(2)=90=Ta+(120-90)e^-2t

As for the rest if i can get the equation i will be able to solve!