Let <span class="katex-r" data-latex="displaystyle vec{F} = (x^4 + 4xy^3)vec{i} + (6x^2y^2 - 5y^4)vec{j}"></span> be a vect field.(a) Calculate <span class="katex-r" data-latex="displaystyle text{cl } vec{F}"></span> and <span class="katex-r" data-latex="displaystyle text{div } vec{F}"></span>.(b) F∈d a function <span class="katex-r" data-latex="displaystyle f"></span> such that <span class="katex-r" data-latex="displaystyle nabla f = vec{F}"></span>.