Prepositions to describe changes

Profits decreased ___ 10 ___ 4.

• from... to

• from...till

• at...by

There was a drop ___20 units.

• on

• of

• to

It dropped ____ 9 units.

• on

• too

• by

A decrease ___ the number of faulty produce

• in

• on

• at

I was working at university ____ 2008 ____2011

• from... to

• between... and

• from... in

I was studying at university between 2003 to 2007.

Is this sentence correct or wrong grammar?

• correct

• wrong

The sales started ___ 30 units ___ 2011.

• of... in

• at... in

• in... in

The profits peaked ___ $12,500 dollars ___2006.

• at ... in

• on ... in

• by ... in

The sales dropped ___ 20 units ___ its lowest indicator ___ 12 units in 2008.

• by... to ... at

• on... to... of

The profits increased ___ 400 dollars last year.

• at

• by

• in

• on