Question: Jim Keller is a microprocessor engineer most well known for his work at AMD and Apple, he was involved in designing which 32-bit package on package (PoP) system-on-a-chip (SoC) designed by Apple Inc. and manufactured by Samsung? 
Facts:
Jim Keller (engineer) was involved in designing the Apple A4 processor
Apple A4 was designed by Apple Inc.
Apple A4 was manufactured by Samsung
Answer: Apple A4