The famous scientist Galileo Galilei did several experiments with sloping planes, which he rolled metal balls down so that he could study motion. By changing the slope, he could study how the speed at which the ball rolled was affected. What was the independent variable in Galileo's experiment?
1. the speed of the ball
2. the slope of the plane
3. whether the ball moved
4. what the ball was made of

6. in domesticated cats, the following are independently assorting: normal ears (t) is dominant to tufted ears (t); curved whiskers (c) is dominant to straight whiskers (c); the presence of six toes (s) is dominant to five toes (s); gene for hair length is an x-linked codominant. the three phenotypes for hair length are long (xhxh), medium (xhxh), and short (xhxh); medium is the heterozygous condition. given two parents: ttccssxhxh x ttccssxhy how many different gametes could be formed in the female cat with respect to these four traits? how many phenotypes are possible in the offspring from this mating?

In general, characteristics that an organism survive and reproduce become more common over time. what mechanism of evolution causes this?

Food webs - transferring energy and matter from one level to another. here you see four food webs. one or more are incorrect. which food web(s) show the correct sequence of organisms, from start to top level consumer? a) a b) d c) c d) a and d