Ineed ! -this is k12 8th grade english

which sentence uses a formal style that is appropriate in an informational piece of writing?

kelly, a big dog lover, decided to start a pet-sitting business, but then realized she hated having to walk the dogs, especially when it rained.

if you launch a product at a trade show, you better not flake on filling orders for your customers.

to become an entrepreneur, you not only need an idea but a business plan that sets goals and objectives for the business.

entrepreneurs need to get a clue about their start-up costs and know someone who can foot the bill for them until the business takes off.