Option B ($29,200) is correct.

X's salary = $550 ÷ 5% = $11,000; Y's salary = $450 ÷ 5% = $9,000

Residual profit = $94,000 − $3,000 + $1,000 − $11,000 − $9,000 = $73,000 (Interest on drawings added back: $550+$450=$1,000)

Y's share = 2/5 × $73,000 = $29,200

Lithium forms only Li₂O (normal oxide). Na forms Na₂O₂ (peroxide); K, Rb, Cs form superoxides (MO₂).

A compressed workweek is any arrangement of work hours that permits employees to fulfill their work obligation in fewer days than the typical five-day workweek (e.g., four 10-hour days instead of five 8-hour days).

The textbook describes two main types of newspaper advertising:

• Classified Advertisements: Brief, text-only ads, usually confined to a single column. They are the simplest form of print advertising — historically used for job vacancies, property rentals, for-sale items, personal notices, and service listings. The term “classified” comes from their organisation into categories (jobs, real estate, vehicles, etc.).
• Display Advertisements: Larger, visually designed ads that can span multiple columns. They include graphics, logos, photographs, colour, and creative layouts designed to attract attention. Display ads are the dominant format for branding and promotional campaigns. The first multi-column display ads in the U.S. were used to promote transcontinental railroad bonds in the 1860s.

The textbook notes that newspapers typically charge display ads in advance, but advertising agencies are given 90-day credit terms. Premium placement (front page, specific positions) can cost up to 400% more than standard rates.

To solve this, you have to break it down into the same "Select then Arrange" flow:

1. Selection ($C$): * We need 3 Physics books. Since P1 is mandatory, we only need to choose 2 more from the remaining 4. Calculation: $\binom{4}{2} = 6$.

   • We need 2 Math books from 4. Calculation: $\binom{4}{2} = 6$.

   • Total selection combinations: $6 \times 6 = 36$.

2. Arrangement ($P$): * We have 5 books (3 Physics, 2 Math).

   • The "Gap Method" is best for the constraint "Math books not together."

   • First, arrange the 3 Physics books: $3! = 6$ ways.

   • This creates 4 possible gaps ( _ P _ P _ P _ ).

   • We must place the 2 Math books into these 4 gaps: $^4P_2 = 12$ ways.

   • Total arrangements per selection: $6 \times 12 = 72$.

3. Final Calculation:

   • $36 \text{ (selections)} \times 72 \text{ (arrangements)} = 2592$.

Correct Answer: D (1200 or more)