Find the Vertex, the Y-Intercept, and the X-Intercepts (If Any $\mathrm { P } ( \mathrm { x } ) = - 3 \mathrm { x } ^ { 2 } + 126 \mathrm { x } - 960$

Find the vertex, the y-intercept, and the x-intercepts (if any exist) , and graph the function.
-The daily profit in dollars of a specialty cake shop is described by the function $\mathrm { P } ( \mathrm { x } ) = - 3 \mathrm { x } ^ { 2 } + 126 \mathrm { x } - 960$ , where $x$ is the number of cakes prepared in one day. The maximum profit for the company occurs at the vertex of the parabola. How many cakes should be prepared per day in order to maximize profit?

A) 42 cakes
B) 441 cakes
C) 1323 cakes
D) 21 cakes