Field notes are used to refresh an officer's memory and are used whin completing the final report. True False

(a) The boys told us they were leaving at 8 p.m.

Montrer que \( \overrightarrow{A^{\prime} B^{\prime}}=k \overrightarrow{A^{\prime} E^{\prime}} \), déchire que \( \overrightarrow{A^{\prime} B^{\prime}}=k \overrightarrow{C^{\prime} D^{\prime}} \)

b) \( \frac{\sqrt{1,3}\left(\frac{5}{4}+\frac{1}{3}\right)}{\left(\frac{6}{5}\right)^{-1}}=\frac{2 x-0,4}{x+1,2} \)

Find the length of the curve \( x=2 \operatorname{Cos}^{3} \theta y=2 \operatorname{Sin}^{3} \theta \) between the points corresponding to \( \theta=0 \) and \( \theta=\pi / 2 \).

Which one of the following hypotheses is/are valid? 1. \( H_{0}: \mu \leq 100 ; H_{1}: \mu \geq 100 \) 2. \( H_{0}: \mu=120 ; H_{1}: \mu \neq 120 \) 3. \( H_{0}: \mu \neq 130 ; H_{1}: \mu=130 \) 4. \( H_{0}: \bar{X} \leq 210 ; H_{1}: \bar{X}>210 \) 5. \( H_{0}: p \neq 0.42 ; H_{1}: p=0.42 \)