What equipment is drilling known to involve?
Is drilling known to involve heavy -duty equipment ,a variety of fluids and sophisticated instrumentation?
Drilling is known to involve heavy -duty equipment ,a variety of fluids and sophisticated instrumentation,is not it?
What is known to involve heavy -duty equipment ,a variety of fluids and sophisticated instrumentation?
Is drilling known to involve heavy -duty equipment ,a variety of fluids and sophisticated instrumentation or computer?