To answer this item, we let x be the number that is not unknown in this item such that the situation in this problem can be expressed as follows,
x - 9.3 = 68.91
Adding 9.3 to both sides of the equation,
x - 9.3 + 9.3 = 68.91 + 9.3
Simplifying,
x = 78.21
The answer to this item is 78.21, this I think is the first choice except that it is mistakenly written as 7.21 only.
<u>Answer:</u>
Crystal structure is a way how atoms or molecules are arranged and in what manner to form a Crystal and this arrangement helps to differentiate one crystal from the other.
Using a crystal structure we can tell that crystal of pyrite is cubic and crystal of gypsum is mono-clinic which helps to tell us that both the crystals are separate from one another because of the arrangement of the molecules and atoms in both.
I think it’s d mark Brainly ist plz
Answer:
Partial melting occurs when only a portion of solid is melted. It is thus enriched in the chemical components of minerals with lower melting temperatures and the remaining unmelted portion of the rock is composed of minerals with highest melting temperatures. Partial melting preferentially enriches melts with incompatible elements.
Partially melted rock do not usually experience complete melting inside the Earth, due to their different chemical composition and their melting points.
It is thought that partial-melting processes play a major role in generating more-defined liquids from less-evolved ones, so that many basalts may be the result of partial melting in the upper mantle, and many granites may have derived partly or completely from the partial melting of continental crust (anatexis).With increasing temperature and pressure, the subducted oceanic crust (of basic composition) first undergoes metamorphism and then begins to melt or release watery fluids; this material rises into the overlying mantle, which may also begin to melt, giving rise to intermediate magma.