A tank initially contains 700 gallons of water in which 5 pounds of salt are dissolved. A salt solution containing 2.5 pounds of salt per gallon is poured into the tank the tank at rate of 5 gal/min. The mixture in the tank is stirred and drained off at the rate of 9 gal/min. (a). Find the initial value problem that describes the amount of salt A(t) in the tank until the tank is empty
(b). Find the amount of salt A(t) in the tank until the tank is empty
(c). Find the concentration c(t) of salt in the tank until the tank is empty
(d). Fin the concentration of salt in the tank at the exact time the tank becomes empty

Which of the following is true for the relation f(x)=2x^2+1

What is the value of x in the following equation? -3x-2=2x+8

1- is the product of two rational numbers irrational or rational? first, make a hypothesis by multiplying two rational numbers. then, use variables such as x=a/b and y=c/d and the closure property of integers to prove your hypothesis. 2- what do you think the product of a nonzero rational number and an irrational number is? is it rational or irrational? make use of variables, the closure property of integers, and possibly a proof by contradiction to prove your hypothesis. 3- why do we have to specify that the rational number must be nonzero when we determine what the product of a nonzero rational number and an irrational number is? if the rational number were 0, would it give us the same result we found in part b?