Bộ lông của loài nào sau đây được sử dụng để trang trí
A.Quạ
B.Vịt
C.Đại bàng
D.Công

\(\mathop {\lim }\limits_{x \to 1} \frac{{\sqrt {1 + 3x} + \sqrt[3]{{1 - 9x}}}}{{{{\left( {x - 1} \right)}^2}}}\)
A.\(\frac{9}{{64}}\)
B.\(-\frac{9}{{64}}\)
C.\(\frac{1}{{8}}\)
D.\(-\frac{1}{{8}}\)

\(\mathop {\lim }\limits_{x \to 0} \frac{{\sqrt[3]{{1 + 3x}} - 1 - x\sqrt {1 - x} }}{{{x^3} + {x^2}}}\)
A.\(0\)
B.\(\frac{1}{2}\)
C.\(\frac{2}{3}\)
D.\(\frac{1}{4}\)

\(\mathop {\lim }\limits_{x \to 2} \frac{{\sqrt[3]{{x + 6}} - \sqrt[4]{{7x + 2}}}}{{x - 2}}\)
A.\(-1\)
B.\(-\frac{17}{95}\)
C.\(-\frac{13}{96}\)
D.\(-\frac{15}{97}\)

\(\mathop {\lim }\limits_{x \to 0} \dfrac{{\sqrt[n]{{1 + ax}} - 1}}{{\sqrt[m]{{1 + bx}} - 1}}\,\,\,\left( {ab \ne 0,m,n \ge 2} \right)\)
A.\(\dfrac{an}{bm}\)
B.\(\dfrac{2am}{n}\)
C.\(\dfrac{am}{2bn}\)
D.\(\dfrac{am}{bn}\)

\(\mathop {\lim }\limits_{x \to 2} \frac{{{x^{2020}} - {2^{2020}}}}{{{x^{2021}} - {2^{2021}}}}\)
A.\(\frac{1010}{2021}\)
B.\(\frac{2021}{2020}\)
C.\(1\)
D.\(0\)

\(\mathop {\lim }\limits_{x \to 1} \frac{{2x - \sqrt {3x + 1} }}{{{x^2} - 1}}\)
A.\(1\)
B.\(\frac{5}{7}\)
C.\(\frac{5}{8}\)
D.\(\frac{8}{7}\)

\(\mathop {\lim }\limits_{x \to 1} \frac{{2x - \sqrt {3x + 1} }}{{{x^2} - 1}}\)
A.\(1\)
B.\(\frac{5}{7}\)
C.\(\frac{5}{8}\)
D.\(\frac{8}{7}\)

\(\mathop {\lim }\limits_{x \to 1} \frac{{\sqrt {3x + 1} - \sqrt {x + 3} }}{{{x^3} - 1}}\)
A.\(\frac{1}{7}\)
B.\(\frac{1}{5}\)
C.\(\frac{1}{4}\)
D.\(\frac{1}{6}\)

Bộ nào trong nhóm Chim bay có mỏ khỏe, quặp, sắc nhọn?
A.Bộ Gà
B.Bộ Ngỗng
C.Bộ Chim ưng
D.Bộ Cú