A real estate investor thinks the real estate market has bottomed out. One of the variables he examined to arrive at this conclusion was the proportion of houses sold at or above the asking price. In 2010, the proportion of houses sold at or above the asking price was 14%. The real estate investor takes a random sample of 40 recently sold houses and finds that nine of them are selling at or above the asking price. 

a. Specify the population parameter to be tested. 

b. Specify the null and alternative hypotheses to determine whether the proportion of houses sold at or above the asking price has increased. 

c. Calculate the value of the test statistic and the p-value. 

d. At the 10% significance level, can you conclude that the proportion of houses sold at or above the asking price has increased?