The Dubai police fleet includes a Lamborghini, Ferrari and Bentley. This is to allow them to catch speeders who can outrun other cars.

Greyhounds can reach a speed of 43 mph in 6 strides.

True - see here

Mosquitoes fly at speeds between 1 and 1.5 miles per hour, making them one of the slowest flying insects of all.

Whip makes a cracking sound because its tip moves faster than the speed of sound.

True - see here

It takes about 20 seconds for a red blood cell to circle the whole body.

True - see here

It takes a sloth a whole month to travel one mile on the ground.

The fastest bird is the peregrine falcon. It can fly at a speed of 168-217 miles per hour.