Correction in essay

hello

I have questions

I'm writing essay and I'm confusing in these sentences

can I say " Previous works have shown that....." I mean can I say previous works or it should be work?

" after the calcution, values for average.....? " can I say values for or I should say values of

" the techniques are not known apriori...?" there is a word in english apriori or it must be a priori???

" when the total increase,............." can I say increase or increases??

" in recent work (1,3,5),..........." can I say recent work or it should be recent works??

I hope that you can help me

thanks alot