Question: what is the cpu for the calculator with 28 kb of ram and display size 128×64 pixels 21×8 characters?
Schema: create table table_11703336_1 (cpu varchar, ram varchar, display_size varchar, PRIMARY KEY (cpu))
SQL: select cpu from table_11703336_1 where ram = "28 kb of ram" and display_size = "128×64 pixels 21×8 characters"