Two people use a ramp to move a heavy box onto a truck. The box weighs 750 N. The mechanical advantage of using the ramp is 4.. How much effort is required to move the box?

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.

a. carbon monoxide from car exhaust

b.particulate matter, such as soot

c.water vapor from a factory smokestack

d.acid rain

these are the answer choices im on that question right now

in most common fires, oxygen is needed for an oxidation reaction to takes place. the combination of oxygen with any element as fuel can create fire and combustion will occur especially if wood, light materials and other combustible things are combine with oxygen.