I want to take two input values and look up the 1st in the A1 column, then
take the 2nd (using the row associated with the first) and find the column (a
value that is less than the 2nd) of the 2nd input. Then output the column
heading. I have a sample table below.

150 Class 300 Class 600 Class 900 Class
Temp Pressure Pressure Pressure Pressure
t1 1 1.5 2 2.5
t2 2 2.5 3 3.5
t3 3 3.5 4 4.5
t4 4 4.5 5 5.5
t5 5 5.5 6 6.5
t6 6 6.5 7 7.5

So, if input 1 is "t2" and input 2 is 2.9, I want an output of "600 Class"

Any help on this is greatly appreciated.

Charlie