Robert and Dora need to write 4,300,000,000 using scientific notation. Robert claims that 4,300,000,000 = 4.3 x 108 and Dora claims that 4,300,000,000 = 4.3 x 109. Which of the following best describes whose number is correct and the reason it is correct?

Robert is correct

Step-by-step explanation:

we know in scientific notation a positive number goes to the right and if we do 4.3 and we go back the spaces it would be nine spaces so it would be 4.3 X 109

1/3 + 1/3 ≠ 2/6 because 1/3 alone = 2/6  

step by step explanation:

1/3 + 1/3 = 2/3       2/3=4/6

180-142=38 for the acute angle next to the entry

90+38=128

180-128=52

a=52

step-by-step explanation: