Conversion of Units of Measurement

A unit expression is:

• a unit name, such as meter . Common abbreviations such as ft or mph are allowed.
• a number such as 2.5 or kilo
• an expression of the form unit₁ ... unit_n with spaces between items: 60 mph
• an expression with / between units; the units to the left of the / are divided by the units to the right: 60 mile / hour
• parentheses may be used for grouping
• a Lisp-like product of unit expressions, (* unit1 ... unitn)
• a Lisp-like quotient of two unit expressions, (/ unit1 unit2)

For example, a speed of 60 miles per hour could be represented as:

• 60 miles per hour
• 60 mph
• 60 miles / hour
• (* 60 mph)
• (* 60 (/ mile hour))

For temperature conversions, the source must be a product such as 50 F and the goal must be a temperature unit such as C.

Instructions: