CHEMISTRY A chemistry teacher needs to mix an acid solution for an experiment. How much hydrochloric acid needs to be mixed with 1500 milliliters of water to make a solution that is \( 12 \% \) acid? If necessary, round to the nearest hundredth.

4. (Ufal) Abaixo está esquematizada uma representação de um coração humano. Identifique os vasos que trans- portam sangue arterial e aqueles que transportam san- gue venoso. Qual dos ventrículos apresenta musculatu- ra mais espessa e por que isso ocorre?

Question 5 (continued) (d) The weight of two cars together is 4.9 ton. One of the cars weighs 3.3 ton. Find the ratio of the weight of the smaller car to the larger car in its simplest form. ( 2 marks)

Find the rate of change of \( y=9 x^{2}+23 \) at \( x=1 \)

18. Select all expressions equivalent to \( 102.4-\left[\left(2^{3} \times 3\right)+13.8\right] \div 7 \) \( 102.4-\left[\left(3^{2} \times 3\right)+13.8\right] \div 7 \) \( \left(10^{2}+2.4\right)-(37.8 \div 7) \) \( 102.4-\left(6^{2}+1.8\right) \div 7 \) \( 102.4-\left[\left(2^{3} \times 3\right)+20.8\right] \) \( (60+42.4)-[(8 \times 3)+13.8] \times 7 \)

ng trình \( \frac{1}{x}-\frac{3}{2 x}=\frac{1}{6} \) là