If strep bacteria causes the infection, it can remain contagious for up to 2 weeks without treatment. However, antibiotics can shorten the contagious period and li â¦ mits to about 24 to 48 hours once the therapy starts.     http://health.top54u.com/post/How-Long-is-Tonsillitis-Contagious.aspx.
Calculate Options Implied Volatility in Excel. Implied Volatility Function: Returns the annualized volatility of an underlying security implied by the market price of a European call or put option on that security, based on Black-Scholes valuation. Description of parameters.
Go with the cash flow: Calculate NPV and IRR in Excel - Choosing the appropriate Excel function. 1  Which Office Excel functions can you use to calculate NPV and IRR? There are five: NPV, XNPV, IRR, XIRR, and MIRR. 2  Note Cash flows are specified as negative, positive, or zero values.