Can anyone help me solve these 4 questions involving scale factor? Worth 40 pts.

2. A photographer takes an aerial photo of a field on which a circular crop plant has been planted. He prints the photo out and notes that 2 centimeters of length in the photo corresponds to 100 meters in actual length.

2a. What is the scale factor of the actual farm to the photo?

2b. If the dimensions of the entire photo are 25 cm by 20 cm, what are the actual dimensions of the rectangular land area in meters captured by the photo.

2c. If the area of the rectangular photo is 5 [tex] cm^{2} [/tex] , what is the actual area of the rectangular area in square meters?

3. A store is having a sale to celebrate President's Day. Every item in the store is advertised as one-fifth off the original price. If an item is marked with a sale price of $140, what was its original price? Show your work.