Answer
(a) 1.3 cm
(b) 5 cm
Work Step by Step
We use unit conversions to solve the problem. To do this, we multiply by different fractions until every unit except the final unit we want is cancelled out. Doing this, we find:
$$=13 \ mm \times \frac{cm}{10 \ mm} \\ = 1.3\ cm$$
For the mouse:
$$=50 \ mm \times \frac{cm}{10 \ mm} \\ = 5\ cm$$
