Inverse normal distributions question (STATS 1 AS LEVEL)?

I'm not familiar with all your terminology but the question is describing a normal distribution centred on (TimeOfEntry + 245) and where 1pm is towards the right hand side with 0.98 of the area to its left and 0.02 to its right. Thus from the time of entry, 0.98 of all purchases will have occurred by 1pm.