By Pleistocene ice age is meant the glacial periods that appeared in the Pleistocene. The Pleistocene is the first epoch of the Quaternary. It is an epoch when there was a so called ''ice age'' on the Earth, or rather a glacial period. During this ice age the planet had much lower temperatures on a global scale. The climate was also much drier. Lot of ocean water was frozen in the ice sheets that were stretching deep into the North American and Eurasian continents, which resulted in much lower sea levels that today as well. The places further north than 40 degrees of latitude were almost exclusively covered with ice, so life was almost impossible apart from some coastline places.
Answer:
B. 4 Fe + 3 0₂---> 2 Fe₂O3
Explanation:
(A) Ir + O₂--> IrO₂ No: Ir is iridium
(B) 4 Fe + 3 0₂---> 2 Fe₂O3 Yes: Fe is iron and O is oxygen, and the equation is balanced.
(C) I+ 0₂ ---> 10₂ No: I is iodine
(D) 3 Ir + 0₂ -> 6 Ir₂03 No: I is iodine
Answer: A) Na+ and O2-
Explanation:
To know the electronic configuration, one has to determine the numbers of electrons present in each atom.
Na+ means a sodium atom that has lost one valence electron. A Sodium atom initially has 11 electrons, but having lost an electron making it 10 electrons remaining with electron configuration of 1s2 2s2 2p6.
O2- means oxygen atom that has gained two valence electrons. An oxygen atom initially has 8 electrons, having gained two electrons makes it 10 electrons with electron configuration of 1s2 2s2 2p6. same as Na+
The purpose of gaining or losing electrons is to attain a stable duplet or octet structure.
<span>As far as I remember, cell-mediated immunity differs from humoral immunity in that </span>they respond differently to invaders
Answer:
Nonpoint-source-pollution
Explanation: