Answer:
The porch is 7.35 feet off the ground
Explanation:
Trigonometric Ratios
The ramp, the height of the porch, and the distance from the base of both form a right triangle where trigonometric ratios can be applied.
The angle of 20° has the height of the porch H as the opposite side, and the hypotenuse is the length of the ramp.
The sine is defined as:

For our problem:

Solving for H:

Find the sine of 20° by using a calculator:

H=7.35 feet
The porch is 7.35 feet off the ground