What role do salmon play in the nitrogen cycle? Why are the empty survey nets of concern? pls help! need it by 10:15!

Florian discovers a rock that is broken into pieces. each piece has several bands. which type of rock does florian predict these pieces will change into when subjected to heat and pressure? igneous magma metamorphic sedimentary

Living cells cannot use heat to provide the activation energy for biochemical reactions because which choice(s) complete the sentence correctly? a) answer choice ii. eliminate b) answer choices ii and iv. c) answer choice iii and iv. d) all answers can complete the sentence.

Which of the following must be true for a fossil organism to be useful as an index fossil? a. the fossil organism must be widespread geographically. b. the fossil organism must be abundant. c. the fossil organism must be limited to a short span of geologic time. d. all of the above.