Please help i cant figure it out

Who needed protection from railroads? 1865-1900 apush

If pressure and temperature remain constant, will the volume of gas in the respirometers increase or decrease?

Which part of each sentence is a dependent clause? the boys didn’t think dani could win the race even though she was on the school track team. trisha went down to the farmer’s market so she could get some apples. after he was injured by a stray ball, alex was sent to the nurse’s office. though he hated math, chris tried to do the equations.