can someone please explain why in some of these examples cash is in the beginning of the entry and for others it comes in the second line.

1. Invested $100 cash in business 2. Purchased used car for $2,000 3. Purchased supplies on account for $500 4. Paid $350 cash for advertising 5. Billed customer $5,000 for services performed 6. Received $2,000 payment for bill in #5 Capital IDD 2.) Equip. Car 2000 3.) Supplies A/P