A radioactive substance has a half-life of 5,000 years. If the original sample contained 20 grams of the radioactive isotope, how much remains after 5,000 years have elapsed

What will most likely happen in the absence of a cell membrane? a) photosynthesis will not take place. b) the cell will not store food, water, nutrients, and waste. c) energy will not be released during cellular respiration. d) substances will pass in and out of the cell in an uncontrolled manner.

40dm3 of gas at 760 torr are heated from 5°c to 50°c what is the new volume

Need asap question 1 minerals are organic compounds. true false question 2 what vitamin can be found in foods like oranges, grapefruits, and broccoli? a. vitamin a b. vitamin k c.vitamin c d. vitamin d question 3 what are minerals? a. chemical elements that are needed for body processes. b. organic compounds that the body needs in small amounts to function properly. c. small molecules used to build proteins. d. an organic compound that is insoluble in water and includes fats. question 4 how many types of vitamins does the human body need? a. 15 b. 11 c. 13 d. 17 question 5 vitamins are a good source of energy. true false