According to splash page: Reprints Showcase #11 (Nov-Dec, 1957)
Contains:
The Day the Earth Blew Up, Pt. 1. (pg. 1)
The Tyrans, Pt. 2 (pg.9)
The Thing that Came Out of the Sea, Pt. 3 (pg.18)
One Minute to Doom, Pt. 4 (pg. 25)