Gọi kim loại đó là: $R$

$R+2HCl\to RC{l}_2+H_2\uparrow$

$0,15$                              $0,15$       $\left(mol\right)$

$n_{H_2}=\frac{3,36}{22,4}=0,15\left(mol\right)$

$\Rightarrow M_R=\frac{6}{0,15}=40(g/mol)$

    $\to R$ là $Ca$

1. collection

2. collectively

3. collector

4. collection

5. nicest

6. nicely

7. hurriedly

8. hurry

9. hurried

Ta có: $\{\begin{array}{c}{p}_A+e_A+p_B+e_B=92\\ p_A-p_B=6\\ p_A=e_A\\ p_B=e_B\end{array}$

$\iff \{\begin{array}{c}{p}_A=e_A=26\\ p_B=e_B=20\end{array}$

a: $=2\left(x^2-\frac{1}{2}x+\frac{1}{2}\right)$

$=2\left(x^2-2\cdot x\cdot \frac{1}{4}+\frac{1}{16}+\frac{7}{16}\right)$

$=2{\left(x-\frac{1}{4}\right)}^2+\frac{7}{8}>=\frac{7}{8}$

Dấu '=' xảy ra khi x=1/4

b: $=3x^2-x$

$=3\left(x^2-\frac{1}{3}x\right)$