Because technically there is no such thing as cold
all that exists is heat
this is because heat is the rapid movement of particles, made by friction (to understand why you must delve into physics and some chemistry)
so, when you feel cold, it's really the absence of heat
so instead of "keeping the cold out", which makes no sense at all scientifically, insulation keeps the heat in.
as a side note
the feeling of cold is produced when you come in contact with an object (yes, air counts) that has less heat, or energy, than you do, You feel cold because heat (energy) from your body is being transferred to the environment. This ABSENCE OF HEAT in your body is why you feel cold
Most of the information of the interior
Most of the information about the composition of the earth
Uses energy responds to the environment
The first one. Although I would have phrased it as plants absorbing sunlight and then converting it intro glucose, the type of food that plants can store and then break it down to use as food. but your explanation works fine.
