CREATE TABLE "table1_15928363_1" (
  "vertical" real,
  "horizontal" real,
  "aspect_ratio" text,
  "pixel_aspect_ratio" text,
  "form_of_scanning" text,
  "framerate_hz" text
);

Question: Name the aspect ratio for 720
SQL: SELECT "aspect_ratio" FROM "table1_15928363_1" WHERE "horizontal"=720;

Question: Name the number of horizontal when framerate hz is 25
SQL: SELECT COUNT("horizontal") FROM "table1_15928363_1" WHERE "framerate_hz"='25';