Distance between capitals and cities within country

I would like to have the distance between each capital and the cities within each country. I have the following variables: COUNTRY, capital, and governate and my dataset is called "data".

COUNTRY     capital               governate
1      LIBYA     Tripoli                    <NA>
2     KUWAIT Kuwait City               Farwaniya
3    ALGERIA     Algiers                    Mila
4      LIBYA     Tripoli                    <NA>
5     KUWAIT Kuwait City               Al Asimah
6      SUDAN    Khartoum              White Nile
7  PALESTINE    Ramallah                  Jerico
8      EGYPT       Cairo                    Suez
9    MOROCCO       Rabat Grand Casablanca-Settat
10    KUWAIT Kuwait City               Farwaniya