how do some calls become brain cells and other become skin cells, when the DNA in ALL the cells is exactly the same. In other words, if the instructions are exactly the same, how does one become a brain cell and another a skin cell?

This graph gives information on changes in sea ice extent in the arctic ocean over a 30-year span. the overall trend shows in the ice extent. to address the trend, scientists need to ask themselves, one direct consequence of the trend is that

How many moles of carbon dioxide will form if 2.5 moles of c3h8 is burned

Which of the following is an example of physical change not a chemical change? a) a log gives off heat and light as it burns. b) a tree stores energy from the sun in its fruit. c) a penny lost in the grass slowly changes color. d) a water pipe freezes and cracks on a cold night.