2.3.11 Gradient and directional derivative

Problem: Function $z=z(x,y)$, point $A(x_0;y_0)$ and vector $\overrightarrow{a}$ are given . It is required to find at point $A$ : a) the gradient of the function and its value, b) the derivative of $z$ in the direction of vector $\overrightarrow{a}$. $$z(x,y)=2x^2+3xy+4y^2,A(2;-2),\overrightarrow{a}=\{1;3\}.$$