Answer:
A boundary is a real or imaginary line that separates two things. In geography, boundaries separate different regions of the Earth.The most obvious type of boundary is a physical boundary. A physical boundary is a naturally occurring barrier between two areas. Rivers, mountain ranges, oceans, and deserts can all serve as physical boundaries. Many times, political boundaries between countries or states form along physical boundaries. For example, the boundary between France and Spain follows the peaks of the Pyrenees Mountains, while the Alps separate France from Italy.
The Strait of Gibraltar is the boundary between southwestern Europe and northwestern Africa. This narrow waterway between the Atlantic Ocean and the Mediterranean Sea is an important political, economic, and social boundary between the continents.
Rivers are common boundaries between nations, states, and smaller political units such as counties. The Rio Grande forms a large part of the boundary between Mexico and the United States. The Mississippi Riveris the defining boundary between many of the states it winds through, including Iowa and Illinois, Arkansas and Tennessee, and Louisiana and Mississippi.
Trace fossils provide us with indirect evidence of life in the past, such as the footprints, tracks, burrows, borings, and feces left behind by animals, rather than the preserved remains of the body of the actual animal itself. so i would say B.
Answer:
That involve the complete transfer of an electron from one atom of an element to another
Explanation:
Upon dissolution of KCl heat is generated and temperature of the solution raises.
Therefore, heat generated by dissolving 0.25 moles of KCl will be as follows.

= 4.31 kJ
or, = 4310 J (as 1 kJ = 1000 J)
Mass of solution will be the sum of mass of water and mass of KCl.
Mass of Solution = mass of water + (no. of moles of KCl × molar mass)
= 200 g + 
= 200 g + 13.625 g
= 213.625 g
Relation between heat, mass and change in temperature is as follows.
Q = 
where, C = specific heat of water = 
Therefore, putting the given values into the above formula as follows.
Q = 
4310 J =
Thus, we can conclude that rise in temperature will be
.
1. Berkelium(Berkeley, CA) 2. Dubnium(Dubna, Russia) 3. Darmstaditum (Darmstadt, Germany) 4. Erbium(Ytterby, Sweden) 5. Strontium(Strontian, Scotland) 6. Terbium(Ytterby, Sweden) 7. Yttebium(Ytterby, Sweden) 8. Yttrium(Ytterby, Sweden)