[填空题]
A curve y=f(x) passes througzbdoz y(:ab 6*r7an 3rh poinvzv e+xx e/7t5t $\mathrm{P}$(2,7) and has a gradient of $ f^{\prime}(x)= 4 x-3 $.
1. Find the gradient of the curve at point P ;f(x)= .
2. Find the equation of the tangent to the curve at point P; y=kx-b,k= ,b= .
3. Determine the equation of the curve; the equation of the curve is y=ax$^2$-bx+c;a= ,b= ,c= .