Christina, who is single, purchased 100 shares of Apple Inc. stock several years ago for $3,500. During her year-end tax planning, she decided to sell 50 shares of Apple for $1,500 on December 30. However, two weeks later, Apple introduced its latest iPhone, and she decided that she should buy the 50 shares (cost of $1,600) of Apple back before prices skyrocket. (Leave no answers blank. Enter zero if applicable.)

a. What is Christina's deductible loss on the sale of 50 shares? What is her basis in the 50 new shares?

b. Assume the same facts, except that Christina repurchased only 25 shares for $800. What is Christinas deductible loss on the sale of 50 shares? What is her basis in the 25 new shares?