One student did an experiment to find out if fertilizer can make plants grow taller. the steps of the experiment are listed below. take three pots of the same size. fill the pots completely with the same type of soil. plant tomato seeds in the pots of soil. add different amounts of fertilizer to the three pots. keep the first pot inside the house, the second pot under the shade of a tree, and the third pot in direct sunlight. add the same amount of water to the pots every day. measure the heights of the plants after regular intervals. the results of the experiment were not valid. which of these statements best describes a flaw in the experiment?

Mr. j, age 42, is a construction worker in las vegas. he recently noticed that a mole on his face seemed to be getting larger and darker. at first he did not worry because he was in the sun a lot and assumed the change may have been caused by sunburn. after a month, not only was the mole larger and darker, but it appeared to be “bumpy.” his doctor diagnosed a malignant melanoma skin cancer following biopsy of the nevus. mr. j reports pain in his right shin that does not go away when he puts his feet up or sleeps. discussion questions 1. relate mr. j’s skin changes to the warning signs for malignant melanoma. (see malignant melanoma.) 2. discuss the normal progression of this malignancy. what is the significance of the bone pain that mr. j is experiencing? (see malignant melanoma.) 3. discuss the treatment available for this patient and the prognosis for recovery. (see malignant melanoma.)