Which of the following is true about natural selection? a.) it occurs extremely rapidly b.) it can always be observed within a single generation c.) it causes mutations to occur d.) it causes more useful traits to be passed to offspring

In which situation has the independent variable for the experiment been changed? check all that apply. changed from counting the number of duckweed at day 0 and day 14 to counting them every day changed from testing duckweed growth in beakers to testing duckweed growth in large outdoor tanks changed from testing the effect of ph on duckweed growth to testing the effect of light levels on duckweed growth changed from testing the effect of acid ph on duckweed growth to testing the effect of basic ph on duckweed growth

Ihave a density of 1.61g/cm^3 and a mass of 28g. find the missing value

An object resting on a table weighs 100 n. with what force is the object pushing on the table? with what force is the table pushing on the object? explain how you got your answer.