SOMEONE PLEASE HURRY AND HELP ME

Atank contains 240 liters of fluid in which 10 grams of salt is dissolved. brine containing 1 gram of salt per liter is then pumped into the tank at a rate of 6 l/min; the well-mixed solution is pumped out at the same rate. find the number a(t) of grams of salt in the tank at time t.

Afusion reaction takes place between carbon and another element. neutrons are released, and a different element is formed. the different element is a) lighter than helium.b)heavier than helium.c)the same weight as helium.d)dependent on the element that reacted with carbon.

What would be the original temperature of a gas that has a volume of 2.0 l and a pressure of 2.0 atm and an unknown temperature that the volume increased to 3.5 l in its pressure decreased to 1.0 atm if the final temperature is measured to be 11°c