What is used to break DNA into smaller pieces
?

In the laboratory, restriction enzymes (or restriction endonucleases) are used to cut DNA into smaller fragments. The cuts are always made at specific nucleotide sequences. Different restriction enzymes recognise and cut different DNA sequences.

restriction enzymes (or restriction endonucleases) are used to cut DNA into smaller fragments.

Explanation:

The cuts are always made at specific nucleotide sequences. Different restriction enzymes recognise and cut different DNA sequences.

the answer is; comparing the frequency of collisions with and without the device

this makes the anti-collision system an independent variable and the collisions a dependent variable. if there are fewer collisions with an anti-collision system that without, then it can be stated that the system is a success. essentially, collisions under an anti-collision system are compared with the frequency of collisions by cars with the human drivers.

it's diluted or concentrated

in a diluted solution, you can add a lot more solute but in concentrated only a little more can be added