In an experiment, a petri dish with a colony of bacteria is exposed to cold temperatures and then warmed again.

time (hours) 0 1 2 3 4 5 6
population (1000s) 5.1 3.03 1.72 1.17 1.38 2.35 4.08

a. find a quadratic model for the data in the table. type your answer below.

b. use the model to estimate the population of bacteria at 9 hours. type your answer below.

  the   balanced   equation   for   reaction of   ca metal   with   o2 to   produce   cao   is as below

2 ca+ o2→ 2 cao2

  explanation

the reaction is   balanced     since the   number of atoms   in reactant side is   equal to   number of atoms   in   product side.   for   example   they   are 2   atom of   ca in   reactant   side   and   2   atoms of ca   in   the product side.

  the   process   is a   meet the   requirement   of   redox   reaction because :     calcium   is   oxidized   from   oxidation state 0   to 2+   while   oxygen   is reduced from   oxidation   state   0   to 2-

2b2t

explanation:

2b2t