Which statement is true about vectors? a. All quantities in physics are not vectors. b. A vector may have either magnitude or direction. c. The vector's length should be proportional to its magnitude. d. Two vectors can be added only if they have the same direction.

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

Erosion of the beach is normally a slow process. however, in certain situations, large chunks of shore may wash out to sea. what could cause this to happen?

Two solutions of the same uv-absorbing molecule were analyzed by uv-vis spectroscopy on the same instrument using 1 cm pathlength cells. use data from the table to calculate by what percentage the concentration of solution b is compared to that of solution a.sample absorbance at 315nm a 0.45 b 0.80