Water ripple: $2$D optimization

The following two$-$dimensional function represents the height of a water ripple in centimeters as a function of its $x$ and $y$ position in meters away from its point of origin after $5$ seconds.

$f(x,y)=\frac{sin(\sqrt[\phantom{2}]{(x-10{)}^2+(y+2{)}^2})}{\sqrt[\phantom{2}]{(x-10{)}^2+(y+2{)}^2}}$

A$.$ Use an anonymous function for $f(x,y)$ and MATLAB's mesh function. Create a $3$D plot of the ripple from $-6x18$ meters, and $-3x9$ meters.

B$.$ Use an initial guess of $[61],$ find the location of the maximum ripple height using MATLAB's built$-$in function fminsearch. Use fprintf to display the results with $6$ digits to the right of the decimal point $($e$.$g$.$ 'The

maximum height, $x.[$units$],$ occurs at $x=x.[$units$]$ and $y=x.[$units$].\text{'})$

C$.$ Using MATLAB's plot$3$ and hold commands, plot a red asterisk at the maximum in the plot from part a$).$

D$.$ Repeat parts $b$ and $c$ with an initial guess of $-2]$ and a black asterisk.

E$.$ In text answer the question: 'What changes between the two different initial guesses and why?$\text{'}$