The length of one side of a triangle is 3 feet less than twice the length of its second side. The third side is 2/3 of the sum of the lengths of the first 3 sides. Find the length of all three sides if the perimeter is 6.5

The classrooms are trying to raise $1,200.00 for charity. mrs. leblanc's class has raised 50%. mr. patel's class has raised $235.14 ms. warner's class has raised 1/3 as much as mrs. leblanc's class. how much more money is needed to reach the goal of $1,200.00?

Can someone me and plz do the problem

Ibeg you to me 20. a reaction produces 4.93 l of oxygen, but was supposed to produce 1 mol of oxygen. what is the percent yield?