How could a person easily tell which letters had four and which rive pages without opening the envelope? what assumptions did you make

An object of dimensions 50 cm x 40 cm x 0.20 cm has a mass 60g. find its density in g/cm3 and kg/ m3

There are two routes similar in terrain; however, one route has an incline of approximately 28 degrees, and you must decide on which route to take. what is the maximum road grade that your fully loaded ecv can climb?

Automobile fuel efficiency is often measured in miles that the car can be driven per gallon of fuel (mpg). heavier cars tend to have lower fuel efficiencies (lower mpg ratings). which variable (weight or fuel efficiency) is most naturally considered the explanatory (predictor) variable in this context?