80,000.
To round up to the nearest ten thousand, we would see if the next lower place value has a amount either 5 or higher or 4 or lower.
If it’s five or higher, we round up.
If it’s four or lower, we round down.
We can see that the number in the ten thousands place is 8. The number in the place value after 8 is 2.
2<5 so we round down.
The answer is 80,000.
Hope this helps!
The length of BC is also 6 because the rhombus is equilateral or congruent sides meaning each side are equal to eachother
