Blue light with a wavelength of 305 nm is passed through a double slit with a separation of 18 μm. What is the maximum number of nodal lines visible in the entire pattern?

When calculating percentage we need two numbers. one number represents total amount of certain thing and another number represents partial number of that thing. then we divide those two numbers.in this problem total amount represents total number of weeds growing on some surface. partial number represents chicory.percentage = partial / total * 100%percentage = 29 / 98 * 100%percentage = 29.6%our calculation is closest to answer b) so this is our correct answer.

Idon't understand, it is confusing.