This weekly report discusses progress made on an engineering project. The student designed a 2-layer PCB circuit using surface mount components including a microcontroller, sound IC, and CO2 sensor. The CO2 sensor output was expanded using a zero-span circuit to interface with the microcontroller ADC. When assembled, the full circuit worked correctly. Strengths included a small footprint using surface mount parts, while challenges were the small size making soldering difficult and the sensor requiring warmup time. Next steps are integrating the circuit into the product structure.