Basically, Keegan is right
when you present 7,492,000,000,000,000,000 in standard form, it is indeed, 7×10¹⁸, the reason Jeff is wrong is because he only counted Os and not the numbers 492 which Keegan rounded to Os. Ok, to simply this 7×10¹⁵ equals 7 000 000 000 000 000, and 7×10¹⁸ is 7 000 000 000 000 000 000 while is closer to thee original answer than Jeff's response.
Please mark BRAINLIEST <em>if you're satisfied</em> with this explanations.