"Sometime within" vs. "In exactly"

Hola Claire 

This is a difficult one because the idea of "within" is not that precise in Spanish, but I'd say that:

1. "We will send the exam results out within the next two weeks."

Meaning: at some point before two weeks have passed (could be tomorrow, could be day 13).

Enviaremos los resultados del examen dentro de las próximas dos semanas; 

or

 

Enviaremos los resultados del examen en un plazo máximo de dos semanas. (more formal/precise)

2. "We will send the exam results out in two weeks."

Meaning: exactly after two weeks have passed (around the 14th day).

Enviaremos los resultados del examen en dos semanas. (this may be a bit ambiguous so it may need extra clarification like "no antes de que pasen dos semanas")

or

Enviaremos los resultados del examen dentro de dos semanas. (this implies it's not going to arrive any sooner than that)

I hope this helps. 

Saludos

Inma