Dear All,
	
	Please guide how to calculate the value of N(d1) in following example -
	 
| Number of S.D. from Mean, | (z) Area of the left or right (one tail) | 
| 0.25 | 0.4013 | 
| 0.3 | 0.3821 | 
| 0.55 | 0.2912 | 
| 0.6 | 0.2578 | 
	
	Price of stock now = Rs.80
	Exercise price = Rs.75
	Standard deviation of continuously compounded annual
	return = 0.40
	Maturity period = 6 months
	Annual interest rate = 12%
	
	d1 = 0.5187
	If the value of N(d1) is not given, How to calculate value of N(d1) ?