2. The price-earnings ratio (PE ratio) of a stock is given by

R(x, y) =
where x denotes the price per share of the stock and y denotes the earnings
per share. Estimate the change in the PE ratio of a stock if its price
increases from $60/share to $62/share while its earnings decrease from
$4/share to $3.80/share. (15%)

1.The rectangular region R shown in the accompanying figure 
represents a city's financial district. The price of land in the district
is approximated by the function
p(x, y) = 200 - 10(x - )² - 15(y - 1)²
where p(x, y) is the price of land at the point (x, y) in
dollars/square foot and x and y are measured in miles. What is the
average price of land per square foot in the district? (15%)

6. Solve the equation 4e^t-1 = 4. Then t =___________.