Sigma Sky

engineering economics

Paid

Engineering Economics is often required as an introductory course to Systems Engineering/ Industrial Engineering. In some curriculum, it is also...

electrical engineering 1

Paid

This is a primer for undergraduate Electrical Engineering majors and provides reference for basic electrical engineering and related topics. The...

Logic Op

Paid

Logic Op is a pocket reference for basic digital logic. Features include:+ Logic Gates: references and examples+ Boolean Logic: references and...

write checks

Paid

A little bit of help for those learning how to write checks.