Math help please and thank you :)

173

Step-by-step explanation:

Area of dirt in the flower bed = area of flowerbed - area of 3 trapezoids

Area of flowerbed:

The flowerbed is in the shape of a parallelogram

The area of a parallelogram can be calculated by multiplying the base length times the height

Base length = 20ft

Height = 10ft

Area of flowerbed = 10 * 20 = 200ft^2

Area of rockbeds

The rockbeds are in the shape of trapezoids

The area of a trapezoid can be calculated using this formula

A = (a + b)/2 * h

Where a and b = bases and h = height

The rockbeds of base lengths of 2 and 4 and have heights of 3

So area of rockbeds = (4 + 2)/2 * 3

4 + 2 = 6

6 / 2 = 3

3 * 3 = 9

We then multiply that by 3 ( because there are three rockbeds )

9 * 3 = 27

Finally we subtract the areas

200 - 27 = 173

0.02

step-by-step explanation:

time of 9 192 631 770 periods of the radiation corresponding to the transition between the 2 hyperfine levels of the ground state of the caesium 133 atom at 0 k (but other seconds are sometimes used in astronomy)