Lab 4 pushing java app fails

Hi When i push the roster app as in lab 4 it fails with a error . The error is because of less memory ie 512M allocated to the app , as the heap already takes more memory . 

In the excercise solution video the memory allocated is 750M . 

Now the question is : if in the exam we are asked to push an app with 512 M memory and app doesnt start due to less memory , is it ok that we push the app with more memory? How is the solution evaluated, based on running app or based on memory allocated?

Please advise