Answer:
If the travel time increases to 60 minutes, the optimal giving up time increases.
Explanation:
According to marginal value theorem, marginal value theorem is an optimality model that describes the strategy that maximizes gain per unit time in system where resources, rate of returns decrease with time.
Giving up time is the interval of time between when the animal last feeds and when it leaves the patch. According to the question, if travel time increase to 60 minutes, the optimal giving up time increases as well.