More geometry can someone help me with this

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

Abicycle training wheel has a radius of 3 inches. the bicycle wheel has a radius of 10 inches. approximately how much smaller, in square inches and rounded to the nearest hundredth, is the area of the training wheel than the area of the regular wheel? *

F(x)=5/6x+3 which of the following is true