Answer:
you should have not picked d(t)=10, when t =20, and you also need to pick d(30)=d(70), and everything else seems correct
Explanation:
The reasoning why d(t)=10, when t=20 is because if we rearrange this statement it's the same thing as saying d(20)=10, which if we were simply look at the graph it's a false statement
Secondly the reason why d(30)=d(70) if correct one is because if we were look back at the graph both d(30) and d(70) is equal to an output y value of 40