â The presence of marijuana is detected by a drug test through the presence of the active chemical THC or Tetrahydrocannabinol. Technically, what is detected is known as THC-COOH (11-nor-delta-9-tetrahydrocannabinol-9-carboxylic acid).
1 Average Riding Instructor Salary: Independent riding instructors typically charge an hourly rate for services but on average earn about $35,000 to $39,000 per year.
A: Fitness trainers and instructors make an average of $15.25 an hour or $31,720 a year, as of 2012. The salary depends on the experience, where the trainer w...