Which is Stronger: Enormous or Gigantic?

This comes from my 8 year old's homework, with exact examples from this sheet:



Shades of Meaning



The instructions say to put the following words in order from 'weakest' to 'strongest':



Grumpy, cross, furious

Eat, gobble, nibble

Sip, swig, swallow, gulp

Wreck, destroy, damage

Shining, sparkling, glittering, dazzling

Pretend, fake, phoney

Boring, dull, tedious, uninteresting.

Lump, particle, speck, chunk

Great, big, enormous, gigantic

Awake, sleepy, tired, asleep



Some are obvious while others are completely subjective: Enormous vs. Gigantic? Fake vs. Phoney? Swig vs Swallow? Shining vs. Sparkling vs. Glittering vs. Dazzling? Those all seem like synonyms to me. Am I missing something? Is there some way to definitively determine which word has the 'strongest' meaning?