What are the degree and order respectively of the differential equation satisfying $${e^{y\sqrt {1 - {x^2}} + x\sqrt {1 - {y^2}} }} = C{e^x}$$, (where $$c > 0,\left| x \right| < 1,\left| y \right| < 1$$) ?

What is the curve which passes through the point (1, 1) and whose slope is $${{2y} \over x}$$ ?

If $$x\,dy = y\,dx + {y^2}dy$$, y > 0 and y(1) = 1, then what is y($$-$$3) equal to ?

What is the order of the differential equation $${{dx} \over {dy}} + \int {y\,dx = {x^3}} $$ ?