Key TakeawaysBP ADRs slid in premarket trading Tuesday after the energy giant said its second-quarter earnings will likely be impacted by lower refining margins.The company also expects to take an impairment charge of between $1 billion and $2 billion related to a review of one of its German refineries.Exxon also said refining margins would negatively impact its second-quarter earnings on Monday. BP (BP) American depositary receipts (ADRs) fell in premarket trading Tuesday after the energy giant said that i ...