On TI-84,
2ND VARS 2
normalcdf
lower:2
upper:2.5
m:0
s:1
Paste
scroll down to "Paste", press ENTER
Screen reads
normalcdf(2,2.5,0,1)
press ENTER
Answer: 0.0165403822, round to 0.0165
If you use a table
Look up 2.5 read 0.4938 or 0.9938, (depending on which kind of table).
Look up 2.0 read 0.4772 or 0.9772,
Subtract and get .0166. There is a difference in the 4th decimal place
because the calculator is more accurate than tables.
Edwin