Table: cromemco_specs
Columns: system
year_introduced
s_100_slots
internal_floppy_disk
internal_hard_disk

Question: What is the value for internal floppy disk with s-100 slots greater than 8 introduced earlier than 1978?
SQL: SELECT "internal_floppy_disk" FROM cromemco_specs WHERE "s_100_slots" > 8 AND "year_introduced" < 1978

Question: Which system introduced earlier than 1981 has an internal hard disk of 11 megabytes and less than 21 s-100 slots?
SQL: SELECT "system" FROM cromemco_specs WHERE "s_100_slots" < 21 AND "year_introduced" < 1981 AND "internal_hard_disk" = '11 megabytes'