2. a wilton high school senior was applying to college and wondered how many
applications she needed to send. her counselor explained that with the
excellent grade she received in chemistry she would probably be accepted to
one school out of every three to which she applied. [3 applications = 1
acceptance] she immediately realized that for each application she would
have to write 3 essays, [1 application = 3 essays) and each essay would
require 2 hours work (1 essay = 2 hours). of course writing essays is no simple
matter. for each hour of serious essay writing, she would need to expend 500
calories (1 hour = 500 calories) which she could derive from her mother's
apple pies (1 pie = 1000 calories]. how many times would she have to clean her room
in order to gain acceptance to 10 colleges?

altitude, density, pressure

air gets less dense the higher the altitude and also the air pressure is less as altitude rises.

water   molecules stay close to each other through cohesion, the collective action of hydrogen bonds between water molecules. cohesion plants draw water upwards from the root through the stem's transport tubes (xylem) to the leaf. this transport occurs even in large trees and against gravity. transpiration, evaporation of water from plant leaves, creates a tension on water molecules being pulled up from the stem and roots.

water also has high (the attraction of one substance to another) properties because of its polar nature. adhesion of water molecules to plant cell walls counteract gravity while water is transported from roots to leaves.

water exhibits a very high surface tension when compared to other liquids. surface tension is a property of a liquid that holds the surface together and allows it to resist an external force. by capillary action, the water forms concave menisci inside the pores. the high surface tension of water pulls the concavity outwards, generating enough force to lift water from the roots to the leaves of plants.

thus, cohesion, along with adhesion and surface tension creates a capillary action that keeps water molecules interacting and moving through the plants out to the leaf cells.

therefore, option d) is the correct answer.

explanation:

oxygen, selenium, tellurium, and polonium.

they're all from the same group as sulfur (group 16).