The calendar built-in to Windows could have saved you asking this question - it was a Friday.
April, 25th, 1988, was a Monday.
April 4, 1988 on a Monday.
April 18, 1988 fell on a Monday.
April 22, 1988 fell on a Friday.
April 12th, 1988 fell on a Tuesday.
April 28, 1988 was a Thursday.
August 8 1988 was on a Monday.
January 8 1988 was a Friday.
Monday
8 March 1988 was a Tuesday.
October 8 1988 was a Saturday.
May 8, 1988 was a Sunday.