How much artillery does a nation like Ukraine 'need' to fight Russia

I don’t know military logistics, but I know a lot of nations are giving artillery to Ukraine.

considering the fighting seems to be in the east now, how many pieces of artillery would Ukraine need to fight competently in that region? I get the impression that the US alone gave nearly 100 pieces and other nations are giving pieces of artillery too.

is there a rough estimate of how much they’d need? 500 pieces? how would you determine how much artillery is enough?

The fighting might have moved to the East for now, but it’s unclear what Russia will do next (particularly if it established a land bridge through the Crimea.)

Artillery is distributed between “section de tir” of 3 to 4 guns.
Two “sections” made a “batterie”, with the addition of 6 trucks for logistic an a “section de reco” (ERT) whose role is to prepare the emplacements of fire. A “batterie” support an infantry or armored battalion, the fire is directed by forward observers integrated with the battalion.
So 6 to 8 guns for 500 to 800 fighting men.
As Ukraine count 246 000 men, so 300 to 500 guns. They obviously had their own, the import will replace the loss and permit expansion with reservists.