Why don’t car buyers always choose fuel-efficient vehicles, and how can government regulations encourage them to do so?

fuel efficient vehicles may cost more then other avaliable cars. encouragement can be more advertisement showing why it is worth it or by cutting down non fuel efficient vehicals

not necessarily. higher fitness requires the organism to be reproductive successful. for example, an organism at age 10 with 15 offspring is much more fit than an organism at age 15 with only 5 offspring.

answer >   yes we do, women; have three holes, urethral opening(pee hole, vagina, and the women pee/girls pee out of the urethra like the men do; only they have a single opening to pee/ejaculate.   (sorry if i'm too forward with this, but this is for a biology class, isn't it? )

hope that !         : )