Hello, I'm Tom. I'm ____ and ____. I do exercise every morning. I run for 30 ____. I ____ eat vegetables and fruit. I don't eat too much meat. Because it's ____ for me. I work hard at school and at sports. Sometimes I help my parents at home.
一辆沿直线运动的汽车,原来的速度是v1,一段时间后的速度是v2,用△v表示这一过程中速度的变化量,则下面图中能正确表示这三个物理量关系的是( )
定义在R上的函数f(x)=ex+x3,且f(x+t)>f(x)在x∈-1,+∞上恒成立,则关于x的方程f(x)=f(t)-e的根的个数叙述正确的是( )