**P**,

**Q**,

**R**and

**S**with

**P**<

**Q**<

**R**<

**S**are such that

**P**,

**Q**and

**R**(in this order) are in geometric sequence and

**Q**,

**R**and

**S**(in this order) are in

**harmonic sequence**.

Given that

**S**-

**P**= 40, determine all possible quadruplet(s) (

**P**,

**Q**,

**R**,

**S**) that satisfy the given conditions.