4 Points
The battery in the circuit shown is 9.0 V, and the current flowing through the
circuit is 3.0 A. What is the resistance?

3 Ohms

Explanation:

The following were obtained from the question given:

V = 9.0V

I = 3.0A

R =?

V= IR

R = V/I

R = 9/3

R = 3 Ohms

  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-

he would use the colour black