Finding the Circulation of a Curve in a Solid. (Vector Calculus)

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A solid can in spherical coordinates \begin{equation} x=\rho\sin\phi\cos\theta\\ y=\rho\sin\phi\sin\theta\\ z=\rho\cos\phi \end{equation}

be described by the following inequalities $$0<\rho<1-\cos\phi$$

Let a curve $C$ be the intersection of the boundary surface of the solid with the plane $y=0$ and equip $C$ with an anticlockwise orientation as seen from the positive $y-axis$. Find the circulation

$$\int_{C}(z+e^x)\:dx+e^{x^3+z^3}\:dy+(\sin y-x)\:dz$$

What i tried

The solid is clearly a sphere. Using Stokes theorem i took the curl of the following vector field and i got $$\nabla\times F=(\cos y-3z^2e^{x^3+z^3},2,3x^2e^{x^3+z^3})$$

The normal $n=(0,1,0)$ since the curve lies on the $xz$ plane as $y=0$

Then i took the dot product of $\nabla\times F$ and $n$ to get a value of $2$, which means to say the integral is $2$ times the area of $C$ when projected in the $xz$ plane. Im unsure about my workings though. Could anyone please help me with this. Thanks

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Parametrization of the surface: $$ \eqalign{ x&=\rho\sin\phi\cr y&=0\cr z&=\rho\cos\phi }$$ $$0\le\phi\le\pi,\qquad 0\le\rho\le 1-\cos\phi$$ union $$ \eqalign{ x&=-\rho\sin\phi\cr y&=0\cr z&=\rho\cos\phi }$$ $$0\le\phi\le\pi,\qquad 0\le\rho\le 1-\cos\phi$$

Normal vector in the first chunk: $$N=(\sin\phi,0,\cos\phi)\times(\rho\cos\phi,0,-\rho\sin\phi)=(0,\rho,0)$$

Normal vector in the second chunk: the same.

Parametrization of the curve: $$ \eqalign{ x&=(1-\cos\phi)\sin\phi\cr y&=0\cr z&=(1-\cos\phi)\cos\phi }$$ $$0\le\phi\le\pi$$ union $$ \eqalign{ x&=(\cos\phi-1)\sin\phi\cr y&=0\cr z&=(1-\cos\phi)\cos\phi }$$ $$0\le\phi\le\pi$$ Warning: with this parametrization the orientation of the curve is reversed in the first chunk.

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You don't need to use spherical coordinates up until the surface integral. What you've done seems correct to me now all is left is to calculate the area which can be done in spherical coordinates since the limits of integration are given to you