1) If log 2 =x, log 3 =y and log 7 =z, then the value of log (4.3√69) is : A) 2x+23y −13z B) 2x+23y +13z C) 2x−23y +13z D) −2x+23y +13z Answer: Option BExplanation:log(4.3√63) = log 4 + log (3√63) = log 4 + log (63)1/3 = log (22) + log (7×32)1/3 = 2log 2 +13 log 7+23 log 3 =2x+13z +23y