Step-by-step explanation:
A compound contains atoms of different elements chemically combined together in a fixed ratio. An element is a pure chemical substance made of same type of atom. ... Compounds contain different elements in a fixed ratio arranged in a defined manner through chemical bonds. They contain only one type of molecule.
Answer:

Step-by-step explanation:
Let's use a start by using common denominators.
and 
Now, replace the original equation with the common denominators. 
Solve! 
Answer:
Step-by-step explanation:
Given the equation solved by Morgan, Dakota and Taylor expressed as 7x+5x+1=73, to get the value of x, the valid steps are as shown;
7x+5x+1=73
take the sum of 7x and 5x
12x+ 1 = 73
subtract 1 from both sides
12x+1-1 = 73-1
12x = 72
Divide both sides by 12
12x/12 = 72/12
x = 6
Based on the calculation above, the students with invalid first step is Dakota.
<em>Dakota added 5x with 1 to get 6x which is an invalid step because 1 is not attached to a variable x. A function cannot be added to a constant hence making his first step invalid.</em>
Answer:
65.45
Step-by-step explanation:
Zscore = (x - mean) / standard deviation
x = score
Percentage below C :
D = 18% ; F = 12%
Sum = 30%
Obtain the Zscore for the proportion below D
P(Z < 0.30) = -0.524
Hence, Zscore = -0.524
Put Zscore = -0.524 in the equation :
-0.524 = (x - 72) / 12.5
-0.524 * 12.5 = x - 72
-6.55 = x - 72
-6.55 + 72 = x
x = 65.45
To receive a grade of C or better, score must be atleast 65.45
When You Evaluate the expression you the Answer D) 54