$(1$ point$)$ Are the following differential equations exact? $(You$ have only one attempt! Submit all answers $at$ the same time$)$

$(a)$

$(1-\frac{3}{y}+x)\frac{dy}{dx}+y=\frac{3}{x}-1.$

$(b)$

$(5y-2x)y^{\text{'}}-2y=0.$

$(c)$

$(2ysin(x)cos(x)-y+2y^2{e}^{x{y}^2})dx=(x-si{n}^2(x)-4xy{e}^{x{y}^2})dy.$