Which statements describe what happens when enzymes are added to a chemical reaction? Select all that apply.

- The chemical reaction is sped up.
- The chemical reaction is stopped.
- The activation energy is lowered.
- The enzymes are used up.

The chemical reaction is sped up.

The activation energy is lowered.

Explanation:

When enzymes are added to a chemical reaction, they lower the activation energy needed in the reaction.

In return, that also speeds up the chemical reaction, since less energy is needed to start it.

Enzymes do not stop chemical reactions, and enzymes can also be reused, so they are not used up.

So, the first and third statements are correct.

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.