Final answer:
Lu's gross pay for assembling bikes cannot be determined without additional information such as the hourly rate or number of bikes assembled and the pay per bike.
Step-by-step explanation:
To determine Lu's gross pay for assembling bikes during a week, more information is needed, such as hours worked and rate per hour or details of the payment agreement. Without this information, it's impossible to accurately calculate the gross pay. In mathematical problems involving gross pay calculations, specific details like number of hours worked, the hourly rate, or piece rate (if paid per item assembled) are crucial for determining the final amount earned before taxes and deductions.