What is the solution to question 2 on energy conservation problems homework?

[Mzaa]

Homework Statement

https://www.img.in.th/image/VNYMHY
https://www.img.in.th/image/VNYKDv
This is my homework,but I have a problems with question no.2

Homework Equations

The Attempt at a Solution

I tried to used energy conservation rule to get that the speed is √2gh ,but I don't know how to know the angle after that passing through.

 

[Charles Link]

The parabola has the form $y=ax^2$. They give you that the point B is at $(2H,H)$. That will allow you to compute $a$ and thereby get the slope at $B$.

 

[Mzaa]

Thank you so much! I really forget to use parabola equation.
This is really helpful.