12. What is the purpose of fermentation to the yeast cells? What are the starting material, useful products (for the yeast), and waste products?

Here's ur answer

Explanation:

The purpose of fermentation in yeast is the same as that in muscle and bacteria, to replenish the supply of NAD+ for glycolysis, but this process occurs in two steps: Alcoholic fermentation consists of pyruvate being first converted into acetaldehyde by the enzyme pyruvate decarboxylase and releasing CO2.

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.