A builder builds a house on the land that is 20 feet above sea level. If each floor of the house is 9 feet high, how many feet above sea level is the top of the first floor?

29 feet above sea level

Step-by-step explanation:

One floor is 9 feet high, so the top of the first floor will be 9 feet above the ground.

The ground is also 20 feet above sea level, so add 9 to this to find how many feet above sea level the top of the first floor is:

20 + 9

= 29 feet above sea level

30 units^2

step-by-step explanation:

area is l × w

the length is 3

and the width is 10

3 × 10= 30 units squared

it is contrapositive

i could not see the question too well so check yourself again too . this is because i want you to get it correct.