2cm
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I disagree.... 1 cm at the most.
a thumb tack is about 2 centimeters long.
thumb tack already is an English word.
Thumb tack sinks in water and floats in mercury.
a thumb tack is a simple machine called the lever
Pull it out.
thumb nail, thumb tack, thumb screw, thumb print
it made of cut nails
a thumb tack
This is your chance to become a scientist. Weigh the contents of a packet of thumb tacks, and divide the result by the number of tacks. This will be the average weight of a thumb tack.
Take it to the vet now. That thumb tack can poke or rip holes in your cats organs or get stuck in an organ causing a serious infection.
They are the same thing.
Thumb tack