Answer:
If equal to 90 x is 4
Step-by-step explanation:
Answer:
Place the squares on the rectangle.
Step-by-step explanation:
Hello!
The area of the 1cm by 1cm square is 1 square cm.
We can solve for the area by placing multiple of those squares in the larger rectangle.
If we place it, we get 15 placed squares, with a total area of 15 square cm. This relies on the meaning of area, as we are simply measuring the number of square cm taken up by the object.
We would place 3 rows of 5 squares, representing a height of 3 cm (side length of 3 squares), and a length of 5 cm (side length go 4 squares).
This also proves the area formula A = L * W, as we multiple the side lengths to find the number of square units.
<span>As the age of the U-235 sample is 2.631 billion years, and the half-life of U-235 is 713 million years, the sample has undergone 2.361 X 1,000,000,000 / 713 X 1,000,000 = 3.69 half lives. In each half-life the sample reduces to half its original weight according to the radioactive Half-Life Formula:
ln (Nt /N0) = -kt, where N0 = mass of the original weight of radioactive material, Nt = mass of radioactive material at time t, k = decay constant and t = time interval . We have to put Nt/N0 = 1/2 for time interval = half-life.</span>
