My mother _____ French for 3 years when she was a kid.had been studyingwas studyinghas been studyingstudied

My mother _____ French for 3 years when she was a kid.had been studyingwas studyinghas been studyingstudied

When Sarah was 10 years old, she was 130 cm tall.Two years later, her height had increased by 15%.Find Sarah's height when she was 12 years old.

A mother is three times as old as her daughter. Ten years ago, she was five times as old as her daughter. What are their present ages?

A sum was put at simple interest at certain rate for 3 years. Had it been put at 3% lesser ratio,it would have fetch Rs.500 less.Find the sum.

I ___ here for five years, but I’m quitting now due to never receiving any reward for my efforts.a) have been workingb) workedc) was workingd) have worked