Consider a stock with a volatility of its logarithm of o $=30\%.$ The current price of the

stock is $$70.$ The stock pays no dividends. An American call option on this stock has an expiration date $6$ months from now and a strike price of $$65.$ The risk$-$free interest rate r is $5\%,$ compounded continuously.

$1.$ In order to compute the value of the American call option using Black$-$Scholes valuation formula, which of the following are the approximate values of di and dr$?$

a$.0\mathrm{.}5733$ and $-0\mathrm{.}0395$

b$.0\mathrm{.}2720$ and $-0\mathrm{.}3612$

c$.0\mathrm{.}2720$ and $0\mathrm{.}0395$

d$.0\mathrm{.}5733$ and $0\mathrm{.}3612$

$2.$ The price of the American call option using Black$-$Scholes valuation formula is approximately a$.9\mathrm{.}55$

b$.7\mathrm{.}41$

c$.5\mathrm{.}68$

d$.4\mathrm{.}35$

$3.$ Under the same assumptions above, using Black$-$Scholes formula the price of a European put option is approximately

a$.7\mathrm{.}62$

b$.5\mathrm{.}27$

$.4\mathrm{.}24$

d$.2\mathrm{.}95$