Mr. penman had 2/3 liter of salt water. he used 1/5 of a liter for an experiment. how much salt water does mr. penman have left?

Plz hurry evaluate the expression a+b where a=8 and b=19

Two airplanes start at the same place and travel in opposite directions,one at 395 miles per hour and the other at 422 miles per hour. how many hours will it take for the planes to be 2451 miles apart?

Common binomial factor of 6x(3x+7)+5(3x+7)