题目

Last year, Sam’s family made a decision to move to their new house. The jeep was fully packed and they were prepared for a(n) _______ day. All piled into the car, including six-year-old Sam. Sam’s father, Alex, _______ the engine, and the family _______ toward their new home. Alex drove for miles before they needed more supplies. Then they stopped at the nearest supermarket Walmart.Upon driving into the parking lot, they began to ________ for a parking space. The lot was unusually ________, with many cars, shopping carts (购物车), flashing lights and busy people. Sam felt surrounded by amol FeO 与bmol FeS投入V L、cmol/L的硝酸溶液中，恰好完全反应,产生dmol NO气体和Fe(NO3)3、H2SO4的混合溶液,未被还原的硝酸不可能是A.(21a+189b)gB.3(a+b)molC.189(a+b)gD.(VC-d)mol