What is the price of a European put option on a non-dividend-paying stock when the stock price is $100, the strike price is $90, the risk- free interest rate is $5% per annum, the volatility is 35% per annum (continuously compounded), and the time to maturity is 6 months? Use the Black-Scholes-Merton option pricing formula.

One second later, the stock is traded at 101. How would you estimate the new price for the option without the Black-Scholes-Merton option pricing formula?