Question

Another problem is that sometimes astronauts Blank 1 of 3
small tools. Then they have to Blank 2 of 3
until they can get a new one. 3-D printers solve the problem by allowing astronauts to Blank 3 of 3
.

Answer 1

Another problem is that sometimes astronauts lose small tools. Then they have to go without them until they can get a new one. 3-D printers solve the problem by allowing astronauts to print replacements.