Can someone help with problem 7 and 5

Which of the following is not am example of a polymer? protein nylon kevlar concreta

Which one of the following research methods can show cause and effect

What type of relationship exists between the length of a wire and the resistance, if all other factors remain the same? o a. resistance is directly related to length. ob. resistance is directly related to the square of the length. c. resistance is inversely related to the length. d. resistance is inversely related to the square of the length. reset next