The times taken, \(t\) seconds, by 1140 people to solve a puzzle are summarised in the table.

\(\begin{array}{|c|c|} \hline \text{Time (} t \text{ seconds)} & \text{Number of people} \\ \hline 0 \leq t < 20 & 320 \\ 20 \leq t < 40 & 280 \\ 40 \leq t < 60 & 220 \\ 60 \leq t < 100 & 220 \\ 100 \leq t < 140 & 100 \\ \hline \end{array}\)

(i) On the grid, draw a histogram to illustrate this information.

(ii) Calculate an estimate of the mean of \(t\).