【单选题】Patrick lives near two gas stations, Exxon and Shell. If Exxon decreases the price of gas, we predict that the quantity of gasoline demanded at Shell will
A.
decrease because Exxon and Shell gas are complements.
B.
decrease because Exxon and Shell gas are substitutes.
C.
increase because Exxon and Shell gas are substitutes.
D.
increase because Exxon and Shell gas are complements.
E.
not change Exxon and Shell are different brands of gasoline.
【单选题】在80C51单片机中断自然优先级里,级别第1的中断源是 。
【单选题】在80C51单片机中断自然优先级里,级别第1的中断源是 。
【单选题】在80C51单片机中断自然优先级里,级别第3的中断源是 。
【单选题】在80C51单片机中断自然优先级里,级别倒数第二的中断源是______。
【单选题】My dog likes to chase cats." The predicate is
【单选题】在80C51单片机中断自然优先级里,级别倒数第二的中断源是
【简答题】这些问题与Hershey-Chase实验有关:
【单选题】Look ! There are some people _______ a thief. [ ]