The planet earth consists of land formations, large masses of water, gases in the atmosphere, and living organisms.

from a scientific perspective, which makes the planet earth a system?

a.
the planet earth contains both matter and energy.

b.
the planet earth consists of many components that rely and interact with one another.

c.
there are many different components on the planet earth.

d.
the earth is made of materials that scientists want to study.

You carry a 7.0-kg bag of groceries 1.2 m above the ground at constant speed across a 2.7m room. how much work do you do on the bag in the process? (a) 157j (b) 0.00j (c) 185j (d) 82j

This problem has been solved! see the answera non-uniform fire escape ladder is 6.0m long whenextended to the icy alley below. it is held at the top by africtionless pivot, and there is neglibible frictional force fromthe icy surface at the bottom. the ladder weighs 250n, and it'scenter of gravity is 2.0m along the ladder from the bottom. amother and child of total weight 750n are on the ladder 1.5m fromthe pivot. the ladder makes an angle θ with the horizontal. find the magnitude and direction ofa) the force exerted by the icy alley on the ladderb) the force exerted by the ladder on the pivotc) do your answers in part a and b depend on the angle?

In positive numbers less than 1, the zeros between the decimal point and a non-zero number are blank significant