If log3(a),log3(b),log3(c)\log_3(a), \log_3(b), \log_3(c)log3(a),log3(b),log3(c) form an arithmetic sequence, what is true about a,b,ca, b, ca,b,c?
a,b,ca, b, ca,b,c are in geometric sequence
a,b,ca, b, ca,b,c are in arithmetic sequence
b2=acb^2 = acb2=ac
2b=a+c2b = a+c2b=a+c