Answer:
[tex]\frac {2}{21}\ miles\ per\ hour[/tex]
Step-by-step explanation:
Speed is given by dividing distance covered by the time taken. In this case, the distance that the turtle covers is equivalent to 1/21 miles and the time taken is 1/2 of an hour hence speed will be given by [tex](\frac {1}{21})/(\ frac {1}{2})=\frac {2\times 1}{{1\times 21}=\frac {2}{21}\ mph[/tex]
Therefore, the rate is equivalent to [tex]\frac {2}{21}\ miles\ per\ hour[/tex]
