Answer: Fran's speed while swimming upstream = 1.4 km/h
Explanation:
Given: Fran's swimming speed = 2.1 km/h
Speed of river = 0.7 km/h
The direction against the stream is called upstream.
Speed in Upstream = Fran's swimming speed - Speed of river
= 2.1-0.7 km/h
= 1.4 km/h
hence, Fran's speed while swimming upstream = 1.4 km/h