You will get the easy and medium questions right. On a 20-question section, you will likely breeze through the first 17.
ETS engineers its tests. Hard questions that low scorers get right are not re-used. Easy questions that high scorers miss are also dumped.
The bottom line: The hard questions are made for you.
Miss 3 of the 10 hard questions . . . get a 750.
Miss 6 of the 10 hard questions . . . it's a 700.
If you miss all 10 hard questions . . . plan on a 650.
Ten questions will make or break your score. CrushTheTest makes the only prep material exclusively for high scorers.