The radius of a wheel is 0.25 m.

(d) 7000

Distance covered in 1 revolution $=2 \pi r$

$=\left(2 \times \frac{22}{7} \times 0.25\right) \mathrm{m}$

$=\left(2 \times \frac{22}{7} \times \frac{25}{100}\right) \mathrm{m}$

$=\frac{11}{7} \mathrm{~m}$

Number of revolutions taken to cover $11 \mathrm{~km}=\left(11 \times 1000 \times \frac{7}{11}\right)$

$=7000$