How do you try and work this problem?

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?

If eh = hg and hg=16, find the diameter of k

Describe the domain and range of y=2(3)^x-2+5