18. According to the passage, there was a delay between
the time when Harrison arrived at a solution to the
problem of longitude and when he received his reward
because his:

  • F. invention predated the Longitude Act of 1714.

  • G. clock was only one of many successful solutions
    to emerge simultaneously.

  • H. opponents obstructed his efforts to claim the prize

  • J. supporters abandoned him in order to exploit his
    invention for their own financial gain