How many dishes are there on the menu "Zentral Theater Terrace"?
Zentral Theater Terrace is a name of menu;
SELECT SUM(CASE WHEN T3.name = 'Zentral Theater Terrace' THEN 1 ELSE 0 END) FROM MenuItem AS T1 INNER JOIN MenuPage AS T2 ON T1.menu_page_id = T2.id INNER JOIN Menu AS T3 ON T2.menu_id = T3.id