Carry brake fluid from the master cylinder to the brake units.
a. double-walled steel lines
b. rubber hoses
c. double-walled steel lines and flexible hosesd. none of the answers listed

C. Double-walled steel lines and flexible hoses

Explanation:

The brake units consists of;

Double-walled steel lines carry the brake fluid from the master cylinder along the vehicle frame to flexible hoses attached to wheel cylinders.

2h2o2--> 2h2o + o2

this reaction is of the spontaneous decomposition of hydrogen peroxide down into water and oxygen.

add 2 molecules of hydrogen peroxide and 2 molecules of water. since oxygen is naturally diatomic, the total number of atoms of each element is now the same on both sides of the equation so it is balanced.

this may not be entirely correct but let me know.