$($Graph in image$)$

a$)$ Assume M$\text{'}$s monetary weight equals $$4.$ The monetary weight for $I_1$ and $I_2$ is $$2$ each; the monetary weight for $I_3$ and $I_4$ and is $$3$ each. Where, if any, is the Nash Equilibrium?

b$)$ Now assume the stretch between $H_2$ and $I_4($both points included$)$ were a Nash Equilibrium Assume the same monetary values as under $($a$)-$ only the monetary value of $I_4$ can change. What is the value of $I_4$ to attain the required equilibrium?