The correct option is A 10500
Isabella covers 1.5 km each day.
∴ In 7 days, she will cover 7×1.5 km.
Let's multiply 7 with 15 first.
7×15=105
As the decimal point of 1.5 is in the left of ones place digit of 15, the decimal point in the multiplication should be in left of ones place digit of 105, i.e., 10.5 km.
∴7×1.5 km=10.5 km
Now, as the answer is required in meters, we need to convert the unit.
We know, 1 km=1,000 m∴10.5 km=10.5×1000 m⇒ 10.5 km=10,500 m