We are given a trapezoid TRHY.
Height of the trapezoid = 13 units.
b1 = 21 units and
Area = 215 units squares.
We need to find the length of b2.
We know formula for area of a trapezoid.

Plugging values in formula.
215 =
(21+b2)× 13.
215 = 6.5(21+b2)
Dividing both sides by 6.5, we get

33.08 = 21+b2.
Subtracting 21 from both sides, we get
33.08-21 = 21-21+b2
b2 = 12.08.
<h3>Therefore, length of b2 is 12.08 units.</h3>
Add the exponents and keep the same base. Then reciprocal it and change the sign of the exponent. Then the value of the exponent expression is 0.5.
<h3>What is an exponent?</h3>
Exponential notation is the form of mathematical shorthand which allows us to write complicated expressions more succinctly. An exponent is a number or letter is called the base. It indicates that the base is to raise to a certain power. X is the base and n is the power.
The exponent expression is 2³ × 2⁻⁴ can be simplified.
Add the exponents and keep the same base. Then we have
2³ × 2⁻⁴ = 2⁽³⁻⁴⁾
2³ × 2⁻⁴ = 2⁻¹
Then find the reciprocal and change the sign of the exponent.

The value is 0.5.
More about the exponent link is given below.
brainly.com/question/5497425
The answer is 4,000 ft squared because since the sides are 100 ft and 80ft then we need to multiply them which is 8,000 then divide that by 2 since it’s a triangle which is 4,000 ft squared.