What are the domain and range of the function f(x)=-3(x-5)^2+4

What is the standard deviation of the following data set rounded to the nearest tenth? 3, 17, 18, 15, 12, 21, 9

Which system of linear inequalities is represented by the graph? + l tv x-3y > 6 and y > 2x o x + 3y > 6 and y o x-3y > 6 and y> 2x o x + 3y > 6 and y > 2x + 4 la +

Can someone check if i did this right since i really want to make sure it’s correct. if you do you so much