Which is required of the president by the constitution?

a) to carry out only those federal laws relating to the military
b) to carry out any law supported by the party
c) to carry out all federal, state, and local laws
d) to carry out all federal laws passed by congress and signed into law

Currently, as of february 2016, an american traveling in france would be by the exchange rate. the weakness of the euro and the strength of the us dollar means that items in france cost less to an american than they otherwise would. of course, if this trend reverses and the us dollar weakens and the euro strengthens, such as was happening in early 2008, an american traveling in france would have an adverse experience because items would cost relatively more.