Can someone help me to find the answer

The multiplication property of zero states that the product of any number and 0 is 0. what must be true about either a or b to make ab=0

Jose bought 20 shares of netflix at the close price of $117.98. in a few years, jose sells all of his shares at $128.34. how much money did jose make? a.) $192.50 b.) $207.20 c.) $212.50 d.) $224.60

Polynomial that can be factored as (3x-4)(3x+4)