CREATE TABLE table_64030 ("Class to 1928" TEXT, "Class from 1928" TEXT, "Seats" TEXT, "Quantity" FLOAT, "Year ( s )  of Manufacture" TEXT, "Remarks" TEXT)

What were the remarks for the coach having a class from 1928 of Cid-21B?
SELECT "Remarks" FROM table_64030 WHERE "Class from 1928" = 'cid-21b'
SELECT "Remarks" FROM "table_64030" WHERE "Class from 1928" = 'cid-21b'