What is the area of the given trapezoid abcd? a. 28 in2 b. 56 in2 c. 112 in2 d. 110 in2

STEP-BY-STEP SOLUTION:

To begin with, let's established the formula for the area of a trapezoid / trapezium as displayed below:

A of trapezoid = [ h ( a + b ) ] / 2

Now, let's substitue the values from the equation into the formula and then solve accordingly as displayed below:

h = 4
a = 6
b = 22

A = [ h ( a + b ) ] / 2
A = [ 4 ( 6 + 22 ) ] / 2
A = [ 4 ( 28 ) ] / 2
A = 112 / 2
A = 56 in2

Therefore, the answer is:

Option B. 56 in2

In pure water, the concentration of hydronium ions, or H⁺, will equal the concentration of hydroxide ions. That is [H⁺] = [OH⁻].

Remember that Kw = [H⁺][OH⁻] for water and if [H⁺] and [OH⁻] are both equal, we can easily solve for them by taking the square root of Kw.

[H⁺] = [OH⁻] = sqrt(1.47*10^-14) = 1.21*10^-7

The concentration of hydroxide ions at 30 degrees Celsius is 1.21*10^-7