Student or Learner
1) I will be running a little late for the appointment.
2) Two trays of big rice will give two 8 small bowl of rice. ( What i mean to say is that 2 trays of something will give a certain amount of something after you split them up)
3) Cut the cucmber into julien form/ into cube form.
4) I do not know how his exam/party went.
Not a teacher.
Sentences 1, 3, and 4 seem OK to me. (But Julienne and cube are not the same type of cut.)
For sentence 2, I would use "yield." Two large trays will yield 24 bowls of rice. (Not "big rice.")