In a chemical reaction, substance A decomposes at a rate proportional to the amount of A present. It is found that 8 g of A will reduce to 4 g in 4.7 hours. After how long will there be only 1 g left?

Solve for \( u \). \[ 21 u^{2}-13 u=0 \] Write each solution as an integer, proper fraction, or improper fraction in simplest form. If there are multiple solutions, separate them with commas. \[ u=\square \]

A calculator displays \( 8 E^{-7} \). How do you write \( 8 E^{-7} \) in standard form?

Which equation represents a line which is pempendicular to the line \( y=-4 x-5 \) ? \( \begin{array}{ll}\text { Answer } \\ x+4 y=-32 & 04 x-y--4 \\ 4 x+y=3 & 4 y-x=4\end{array} \)

Multiply. \[ \sqrt{-25} \cdot \sqrt{-4} \]

Use the accompanying data set to complete the following actions. a. Find the quartiles. b. Find the interquartile range. c. Identify any outliers. a. Find the quartiles. The first quartile, \( Q_{1} \), is \( \square \). The second quartile, \( Q_{2} \), is \( \square \). The third quartile, \( Q_{3} \), is \( \square \). (Type integers or decimals.)