Answer 1

Better you not convert the input to lower() case. Try input as it is.
And one i know is task requires is to round up result to 2 decimal point. So try
print( round( sm*1.07, 2) )

Answer 2

Antonio Mariani ,

> as already mentioned, do not convert input to lower.

> modify the strings in *dict items* so that each of them starts with a capital letter.

> after adding tax, round the total sum to 2 decimal places

Answer 3

I think, task is asking to round up results..! Recheck description again..