um for the Celsius to Fahrenheit you have it as

var %t2 $calc($did(7) - 32)
      var %temp $calc(%t2 * 0.55555555555555555555555555555556)
      did -a Temperature 12 Converstion for $did(5) to Fahrenheit:
      did -a Temperature 10 $round(%temp,2) $+ °

it should be

 var %t2 $calc($did(7) * 1.8)
      var %temp $calc(%t2 + 32)
      did -a Temperature 12 Converstion for $did(7) to Fahrenheit:
      did -a Temperature 10 $round(%temp,2) $+ °