I really need help with these practice questions.

3. Consider the function x) shown in the graph below. (a) For this part, no explanation is needed. Use the graph to calculate the limits: rl-itrg'i' ft\") tl-itrlrll f(.1') (b) For this part, no explanation is needed. Use the graph to calculate the limits: sl-iI-nl'F 19(2) 13.11; f(:|'.'} (c) Carefully answer, with explanation, the following question: For what values T does the following limit not exist? 3'33 Km} 4. Consider the following limit: l a: 2 alrl-rmZ x2 2:." (5) Explain why direct substitution of a: = 2 gives an invalid answer. (b) Calculate the limit, carefully explaining each step of the calculation