```{r pkgs, message = FALSE, warning = FALSE}
library(grid)
```


### Exercise 1.1: Bouncing balls


Draw using `grid.circle` and/or `circleGrob`:

* A grey circle with blue border with the center in the middle of the canvas with the edge touching the border of the canvas
* Two circles on the same canvas: one with diameter of half the page with red color and thick black border that touches the edge of the canvas border and another white circle with radius 20% of the canvas width and thick black border that touches the edge of the other circle


### Exercise 1.2: Sport fields


* Draw a European soccer field layout using `grid`
* Draw a tennis court layout
