Answer:
B
Explanation:
because its says mesozoic era
a core of protons and neutrons surrounds by electrons
1.0 *10^(-4) mol
For gases:
n1/n2 = V1/V2
n1/3.8*10^(-4) mol = 230 mL/ 860 mL
n1 = 3.8*10^(-4)*230/860 = 1.0 *10^(-4) mol
