24Alice is considering getting either a used car or a scooter to get back and forth to work. The car and the scooter would be an example of: . threat of substitutions. . bargaining power of suppliers. . rivalry among existing firms. . bargaining power of customers. 25There is only a single drug to treat Henry's disease. This is an example of: . threat of substitutions, strong force. . threat of substitution, weak force. . rivalry among existing firms, weak force. . rivalry among existing firms, strong force. 26 Mary, a teenager, gets $8 per hour for babysitting. Steven lives two doors down and turns 15 next month. Mary is worried that Steven may want to start earning extra money by babysitting, too, and may charge less money. This is a problem of: . bargaining power of suppliers. . rivalry among existing firms. . threat of new entrants. . threat of substitutions