A carpenter uses a crowbar to remove the top of a box the resistance is 500 n he applies a force of 250 N what is the mechanical advantage of the crowbar?

myth. it was once thought that animals, including cats and dogs, could only see in black and white. however, scientists have proven this to be a myth. in all animals, including humans, the perception of colour is determined by the presence of cells in the eye called cone photoreceptors.