The train traveled 100km (50x2) down and then 375km (75x5) up. So the train is 275km (375-100) up from where it started.
Answer:
<u>A chemical bond between the phosphate group of one nucleotide and the sugar of a neighboring nucleotide holds the backbone together. Chemical bonds (hydrogen bonds) between the bases that are across from one another hold the two strands of the double helix together.</u>
Explanation:
<span>Chromated copper arsenate, or CCA, is a pesticide that has been used for years in
pressure-treating lumber to prevent destruction from rot and insects. Arsenic, a toxic
chemical, can leach from this treated wood, leaving residues on the wood’s surface and in
nearby soil. Young children who play on or near decks or playscapes made from CCA-
treated wood can get arsenic on their skin and into their bodies, especially if they eat or
drink without washing their hands.
Because of the health risks of long-term exposure to arsenic, the Environmental
Protection Agency (EPA) has announced that as of December 31, 2003, arsenic Currently the EPA does not recommend that people remove existing structures made with CCA-treated wood or the soil surrounding those structures. However, they do recommend that people reduce their potential exposure to arsenic.</span>
A population will most likely deplete the resources of its environment if the population "increases".