_____________ at home requires only three types of chemicals, several peices of simple equipment, and running water. a. For the development of film b. To develop film c. When film is developed d. In developing film 답은 b 인데 왜그런지...... ______________ often obtain funds from the sale of stocks. a. For corporations to operate b. The operation of corporations c. Corporations operate by d. To operate, corporations 여기서 답은 d 인데 다른것은 왜안되는지. 마지막으로 the approximately 20000 speices of bees 가 맞는 문장인가요?