Consider the marginal value theorem when answering the question below. Optimal giving up time is 30 minutes for an environment with average travel time between patches of 20 minutes. If travel time increases to 60 minutes, the optimal giving up time .

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.  

explanation:

the universal gravitation equation. since the gravitational force is directly proportional to the mass of both interacting objects, more massive objects will attract each other with a greater gravitational force. if the mass of one of the objects is doubled, then the force of gravity between them is doubled.