Christina, who is single, purchased 500 shares of Apple Inc. stock several years ago for $21,000. During her year-end tax planning, she decided to sell 250 shares of Apple for $9,250 on December 30. However, two weeks later, Apple introduced its latest iPhone, and she decided that she should buy the 250 shares (cost of $9,750) of Apple back before prices skyrocket. (Leave no answers blank. Enter zero if applicable.)

b. Assume the same facts, except that Christina repurchased only 125 shares for $4,875. What is Christinas deductible loss on the sale of 250 shares? What is her basis in the 125 new shares?