Rotational Motion: JEE Main 2025 Physics question

A solid sphere of mass 'm' and radius 'r' is allowed to roll without slipping from the highest point of an inclined plane of length 'L' and makes an angle $30^\circ$ with the horizontal. The speed of the particle at the bottom of the plane is $v_1$. If the angle of inclination is increased to $45^\circ$ while keeping L constant. Then the new speed of the sphere at the bottom of the plane is $v_2$. The ratio $v_1^2 : v_2^2$ is