Question

I have three questions, thank you so much for answering or helping!

Answer 1

`4.\text{ }8C2=28`
`\begin{gathered} 5.\text{ they reached }(4)/(5) \\ \text{they n}eed\text{ to go}\Rightarrow1-(4)/(5)=(1)/(5) \\ 1\text{ mile =}(4)/(5)\Rightarrow(1)/(5)=\frac{1}{4\text{ }}mile \end{gathered}`
`\begin{gathered} 6.\text{ a=6, d=3} \\ a_8=a+(n-1)d \\ a_8=6+(8-1)3 \\ a_8=6+21 \\ a_8=27 \end{gathered}`