If a radioactive substance's half-life is 20 years, how much of a 40-gram sample will be left after 60 years? A. 5 grams B. 10 grams C. 20 grams D. 30 grams

Which organelle is the powerhouse of the cell and produces energy? A.) Golgi apparatus B.) Nucleus C.) Mitochondria D.) Ribosome

Tides are the _ and _ of earths water on coastlines and occur regularly so they can be _.

Why was the commons not a problem in the past

The basic building blocks of the nervous system are a. neurons. c. pons. b. medullas. d. glands.

If scientists identify an animal with bilateral symmetry and no segmentation which phylum can it definitely not belong to

What are some examples of comparative anatomy as evidence of evolution?

A group of students is counting the number of plastic bags placed in a landfill during a single day. what are the students doing? A. starting a promblem b. drawing a conclusion c. making a hypothesis d. collecting data by the way this is ecology!

I need some one to rewrite this paragraph (in the comments) to make better sense im currently writing another one atm and this one is due

What following organisms is considered to be an exception to the cell theory

What is the importance of alleles in humans?