Identify the zeros from each function , please help its for today

The circumference of a circle is 5 pi cm. what is the area of the circle?

Aculture started with 2,000 bacteria. after 8 hours, it grew to 2,400 bacteria. predict how many bacteria will be present after 19 hours . round your answer to the nearest whole number. p=ae^kt

Aquadrilateral has exactly 3 congruent sides davis claims that the figure must be a rectangle why is his claim incorrect.