Indicate with a "Yes" or a "No" Which of the Following

Indicate with a "yes" or a "no" which of the following are like- kind exchanges.
a. Computer used in trade or business for office furniture used in trade or business.
b. Apartment building held as an investment for an office building used in trade or business.
c. Land used in trade or business for equipment used in trade or business.
d. Printer used in trade or business for printer used for personal purposes.
e. Exchange of improved real estate held for investment for unimproved real estate held for investment.