如图所示,静止在水平地面上的物体受到的重力为6牛,请用力的图示法画出地面对物体的作用力。
2HCOONa △__ Na2C2O4+H2↑ ①
2HCOONa △__ Na2CO3+H2↑+CO↑②
Na2C2O4 △__ Na2CO3+CO↑ ③
下列说法正确的是( )
— He's never advised to achieve a balance between his job and hobbies, ________? — _______. His parents and teachers often offer him advice.