Find the local maximum and minimum values and saddle point(s) of the function. If you have three-dimensional graphing software, graph the function with a domain and viewpoint that reveal all the...

Extracted text: Find the local maximum and minimum values and saddle point(s) of the function. If you have three-dimensional graphing software, graph the function with a domain and viewpoint that reveal all the important aspects of the function. (Enter your answers as a comma-separated list. If an answer does not exist, enter DNE.) f(x, y) = 4 sin(x) sin(y), -n < x="">< tt,="" -n="">< t="" local="" maximum="" value(s)="" local="" minimum="" value(s)="" saddle="" point(s)="" (х,="" у,="" f)="">