Extracted text: 4. Calculate the following conversions: a. The longitude of Naguilian is 120°25'15". What is the standard time (at 120° East) when the local time is 16'19"47? b. If the longitude of a place is 125°13'15", what is the local time at the place when the standard time is 13'42"17' on 13 June 1986?