Step-by-step explanation:
2x+98=180° (angles in straight line )
2x=180-98
x=2/2
x=1
2=28 divide both get 14 . So each cd is 14$. So now 28+28=56 (4 cd's) plus 14 (1 more cd) =5 so 5 is 70.
Answer: D
Step-by-step explanation:

Answer:
81 900 000 000 000 is 8.19 × 10¹³
Step-by-step explanation:
Write the first number 8.
Add a decimal point after it: 8.
Now count the number of digits after 8. There are 13 digits.
So, in standard form: 81 900 000 000 000 is 8.19 × 10¹³