Question

It is usually justifiable to ignore the difference between $\Delta H$ and $\Delta U$ of condensed phases, except at very high pressure when $PV$ is no longer negligible.
If true enter 1, else enter 0.

Answer 1

True.

$\Delta H=\Delta U+P\Delta V$

For condensed phases, change in the volume of the system is very negligible. So at lower pressure, $P\Delta V$ term is negligible. But at higher pressure it will have some finite value and can't be neglected.