I do believe the answers in a row are A: x, B: 40, C: 12, D:y
Answer:
Step-by-step explanation:

The answer to the equation is X= 27
For 44
7x2=14
14+8=22
22x2=44
Is this ok, I hope I helped :)
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