Read the data on robot reaction times to simulated malfunctions into the data frame t by the following R command

```

```{r}

t = read.table("RobotReactTime.txt", header = T)

```

Read the reaction times of Robot 1 into the vector t1 by

```{r}

attach(t)

t1 = Time[Robot==1]

sort(t1)

```

Using the sorted data and hand calculations

(a) estimate the population median and the 25th and 75th percentiles

(b) estimate the population interquartile range, and

(c) find the pdercentile of the 19th ordered value.