1 Supplies/Resources such as food and equipment are sent to the ISS from Earth.
2 Hawking believes we can pass/overcome all
the problems and colonise space.
3 Some scientists believe a huge asteroid or
comet could extract/wipe out life on Earth.
4 There are many options for colonising space;
the possibilities are endless/continuous.
1) Supplies
2) Pass
3) wipe
4) endless