Answer:  Nina's pick up truck carry's more weight. 
Explanation:
We know that 1 ton = 2,000 pounds
Given:  Brent's truck can carry the maximum weight=
 ton
 ton
In pounds, The maximum load can be carried by Brent's truck =
 
 
 Nina's truck can carry the maximum weight = 500 pounds
Clearly, 

Therefore, Nina's pick up truck carry's more weight.