不等式组$\left\{\begin{array}{c}x<8\\ x>m\end{array}\right.$有解，m的取值范围是____ 

质量相等的无色液体，分别倒入三只相同的烧杯中，如图所示，则三种液体的密度关系是（）

    Jenny is Mr. White's little daughter. She is good at Art . But she isn't good at Math. Mr. White is teaching her ,”What's six plus three?”

    Jenny counts her fingers and answers ,”It's nine .”

    “Good .What's twenty minus three?”

    Anna counts her fingers and toes. “Mm.it's five .No , it's seventeen .”Jenny answers slowly.

    “What's eleven plus twelve, then ?”Jenny looks at her fingers and toes . They are not enough (足够). Seeing this , Mr. White isn't glad and says, “Use your head, Jenny .”

    “That's not enough .I've got only one head.”

根据短文内容，判断下列句子是否正确。

据统计，2015年在“情系桃源，好运丹东”的鸭绿江桃花观赏活动中，6天内参与人次达27.8万．用科学记数法将27.8万表示为（　　）