Um objeto de massa igual a 2 kg move-se em linha reta com velocidade constante de 4 m/s A partir de um certo instante, uma força de módulo igual a 2N é exercida por  sobre o objeto, na mesma direção de seu movimento. Em seguida, o objeto colide frontalmente com um obstáculo e tem seu movimento invertido, afastando-se com velocidade de 3 m/s.O módulo do impulso exercido pelo obstáculo e a variação da energia cinética do objeto, durante a colisão, foram, respectivamente:

(UFPR) O lema dos bolcheviques a partir de abril de 1917 era “Paz, Pão e Terra”, conhecido também como Teses de Abril. Assinale a alternativa que identifica e justifica corretamente qual entre as palavras do lema tem correspondência direta com os acontecimentos da Primeira Guerra Mundial.  

1          What is beauty? Define beauty? One may as well dissect a soap bubble. We know it when we see it - or so we think.

2          Philosophers define ¹it as a moral equation. What is beautiful is good, said Plato. Poets look for high standards. Beauty is truth, truth is beauty, wrote John Keats.

3          Science examines beauty and pronounces it a strategy. "Beauty is health", a psychologist tells me. "It's a sign saying 'I'm healthy and fertile. I can pass on your genes.'"

4          At its best, beauty celebrates. From the painted Txikão Indian in Brazil to Madonna in her metal bra, humanity likes to abandon its everyday look and masquerade as a more powerful, romantic, or sexy being.

5          At its worst, beauty discriminates. Studies suggest attractive people make more money, get more attention in class and are seen as ²friendlier. We do judge people by their looks. In an era of feminist and politically correct values, not to mention the belief that all men and women are created equal, the fact that all men and women are not - and that some are more beautiful than others - disturbs, confuses, ³even angers.

6          The search for beauty is ⁴costly. ⁷In the United States last year people spent six billion dollars ⁸on fragrance and another six billion on make up. In the mania to lose weight 20 billions were spent on diet products and services - in addition to the billions that were paid out for health club memberships and cosmetic surgery.

7          The sad, sometimes ugly side of beauty: In a 1997 magazine survey, 15 percent of women and 11 percent of men sampled said they'd sacrifice more than five years of their life to be at their ideal weight. According to one study, 80 percent of women are dissatisfied with their bodies. In one of its worst manifestations, discontent with one's body can wind up as an eating disorder, such as anorexia or bulimia. Both can be fatal. ⁵Today eating disorders, once mostly limited to wealthy Western cultures, occur around the world, in countries as different as Fiji, Japan and Argentina.

8          The preoccupation with beauty can be a neurosis, and yet there is something therapeutic about paying attention to how we look and feel. "People are so quick to say beauty is superficial", says Ann Marie Gardner, beauty director of "W" magazine. "They're fearful. They say: 'It doesn't have substance.' What many don't ⁶realize is that it's fun to reinvent yourself, as long as you don't take it too seriously". 

"Today" (ref.5) can be substituted by all the alternatives EXCEPT 

Cladogramas são diagramas que indicam uma história comum entre espécies ou grupos de seres vivos. No esquema a seguir, os números representam os ancestrais e as letras, as espécies.

A maior diferença genética será encontrada na sequência de bases nitrogenadas do DNA das espécies