Two cars started their journey at the same time, one started from the Aztec stadium and the other from six flags Mexico. The red car started its journey with a speed of \( 150 \mathrm{~m} / \mathrm{s} \) and the other blue car started its journey with a speed of \( 120 \mathrm{~m} / \mathrm{s} \). We want to know the meeting time of the cars that started their journey and the distance that each of them travels if they were 20,000 metres apart from each other.

Simplify. \( -9 \sqrt{7 a}+3 \sqrt{7 a} \) \( \square \)

18.) \( \lim _{x \rightarrow 0} \sin \left(\frac{1}{x}\right)= \)

(3) \( \frac{d}{d r} \quad\left(22 x^{8}+12 x^{7}+10 x^{3}+10 x^{\frac{5}{2}}+7\right. \)

11. A function \( f \) has \( f(5)=20, f^{\prime}(5)=2 \), and \( f^{\prime \prime}(x)<0 \) for \( x \geq 5 \). Based on this information, which of the following best describes the possible values for \( f(7) \) ? A. \( f(7) \) is greater than 24 . B. \( f(7) \) is less than 22 . C. \( f(7) \) is less than 24 . D. \( f(7) \) is greater than 22 . E. None of these statements describes the possible values of \( f(7) \).

14. Un médico atiende a cada uno de sus pa- cientes en 20 minutos. El día de hoy su horario de trabajo es de 8 a.m. a 12 m . y de 2 p.m. a 5 p.m. y tiene 25 pacientes para consulta. zAlcanzará a atender a to- dos sus pacientes hoy? żCuántos pacientes tendrán que reprogra- mar su cita?