1. Famous poets and writers have claimed for centuries that love stems from powerful emotions. 2.
However, research has shown that feelings of love are at least in part influenced by various
chemicals in the brain. 3. One group of chemicals that is just beginning to be understood is the
pheromones-substances that promote sexual attraction in the opposite sex. 4. Experiments show
that males release a chemical in their sweat that has been shown to be highly appealing to women-
particularly during ovulation. 5. Similarly, women produce their own pheromones that draw men's
interest-one actually can raise the level of testosterone in a man's bloodstream. 6. In addition to
pheromones, another chemical, phenylethylamine (PEA), plays a crucial role in helping people fall"in
love." 7. Related closely to the addictive stimulant drugs called amphetamines, PEA actually causes
people to feel a high from their relationship. 8. The "heart-throbbing" sensations new lovers describe
and the feelings of excitement and infatuation that are part of new relationships are directly
attributed to this chemical. 9. As with many addictive drugs, eventually the body builds up a
tolerance to PEA and the strong feelings begin to wear off, usually within two years. 10. This
explains why infatuation cannot last forever. 11. A third group of chemicals-endorphins-appears to
be at work in long-term relationships. 12. Endorphins are the body's natural pain relievers. 13. In
addition, they produce a sense of security, tranquility, and calm. 14. During physical intimacy,
endorphins are released into the bloodstream, creating the feeling of satisfaction and security
common to long-term successful relationships.

The main idea of the above selection is:

Find the center and the radius of the circle with the equation: x^-2x+y^2+4y+1=0

The basketball crashed against the backboard, and point guard sheena lunged for it. as she snatched the ball out of mid-air, the crowd cheered, chanting encouragement for her team, the monarchs. so far, the game had been a disaster. with 15 seconds left to go in the final quarter, the monarchs were 2 points shy of victory. what main idea do the details in the passage suggest? the point guard sheena was not a very good player. the monarchs had never lost a basketball game. the monarchs were worried about losing. the crowd was not supporting the monarchs.

21) this excerpt involves david, who travels with an inventor named perry. they test their experimental invention, a vehicle that burrows into the earth's crust. which statement best reflects the human experience that is represented in this excerpt? a) humans are not always reliable guides. b) humans desire wealth and a life of ease. c) humans are drawn to explore and experiment. d) humans attempt to conquer and control nature. 22) which statement best reflects the human experience that is represented in this excerpt? a) humans desire to control nature. b) humans are frightened by nature. c) humans are fascinated by nature. d) humans cannot understand nature. 23) 8 “what do you mean perry? ” i cried. “do you think that we are dead, and this is heaven? ” suppose the author changed section eight as listed below. 8 “perry, i have to object! ” i cried. “you don't think that we are dead, and this is heaven, do you? ” which correctly identifies the author's meaning for the word object? consider the effect of the stressed or unstressed syllable in the word object. a) you would stress the second syllable because the word is a noun and means a goal or purpose. b) you would stress the second syllable because the word is a verb and means to express or feel disapproval. c) you would stress the first and second syllable because the word is a verb and means to modify an adjective. d) you would stress the first syllable because the word is a noun and means a thing that has a finite, physical form. 24) 2 together we stepped out to stand in silent contemplation of a landscape at once weird and beautiful. before us a low and level shore stretched down to a silent sea. as far as the eye could reach the surface of the water was dotted with countless tiny isles—some of towering, barren, granitic rock—others resplendent in gorgeous trappings of tropical vegetation, myriad starred with the magnificent splendor of vivid blooms. 3 behind us rose a dark and forbidding wood of giant arborescent ferns intermingled with the commoner types of a primeval tropical forest. huge creepers depended in great loops from tree to tree, dense under-brush overgrew a tangled mass of fallen trunks and branches. upon the outer verge we could see the same splendid coloring of countless blossoms that glorified the islands, but within the dense shadows all seemed dark and gloomy as the grave. which most completely analyzes this excerpt for a comment about life? a) beauty is kind and inviting. b) nature is evil and forbidding. c) there is no risk in following beauty. d) what appears beautiful can also be deadly.