P4 Kaplan Exam Kit – Question 38 Black Scholes

I don’t know if anyone is using the Kaplan materials, but I seem to coming with different answers to the textbook but don’t see any flaws in my workings, question 38 part a for example:

I have d1 = In(28/24)+(0.05+0.5*0.25^2)*2 / 0.25?2 = 0.15415 + 0.08125 * 2 / 0.3536 = 0.4708 / 0.3536 = 1.33144

The text gives an answer of 0.8956

Am I miscalculating somewhere and being too blind to see it or do I have it right?

Any help appreciated.

Michael