11 ft. * 825 ft. significant digits

Which expressions are equivalent to k/2 choose 2 answers: a k-2 b 2/k c 1/2k d k/2 e k+k

David leaves his house to go to school. he walks 200 meters west and 300 meters north. how far is david from his original starting point?

The price of a visit to the dentist is \$50$50. if the dentist fills any cavities, an additional charge of \$100$100 per cavity gets added to the bill. if the dentist finds nn cavities, what will the cost of the visit be?