Answer:
90000 solar cells.
Explanation:
At North America Solar Challenge, if there are 810 solar cars arranged in 9 rows, then there is
solar cars in each row.
Now, given that teams use up to 1,000 solar cells to design and build solar cars for a race.
Therefore, each solar car contains 1000 solar cells to design.
Hence, in 90 solar cars in each row, there will be (1000 × 90) = 90000 solar cells. (Answer)