How does the oceanic crust compare to continental crust? (1) the oceanic crust is thinner and contains less basalt

(2) the oceanic crust is thinner and contains more basalt

(3) the oceanic crust is thicker and contains less basalt

(4) the oceanic crust is thicker and contains more basalt

I think the answer is number (4)

answer; /// i do believe that the correct answer is (a) boiling

answer : (a) volume of the gas = 8.67 ×   l

                (b) second virial coefficient b = -1.21226 l/mole

solution :   given,     t = 300k

                                p = 20atm

                                z = 0.86

                                n = 8.2 mmoles = 8.2 × moles

                                r =   0.082 l atm/k/mol

        find,     (a) volume of gas   and (b) second virial coefficient b at 300k.

formula used :            

                          and            

(a)            

                    = \times 0.082\times 300}{20}[/tex]

                    = 8.67 ×   l

(b)      

                    = (0.00867-1) × 8.659

                    = - 8.5839 l/mole