Using the grammar given above, answer the following questions: 1. (3 points) Modify the above grammar by adding the subtraction operator () with the customary precedence and associativity to the grammar. 2. (2 points) Show that your extended grammar can derive the following sentences: a+bcab+c 3. (3 points) Modify the above grammar by adding the division operators (I) with the customary precedence and associativity to the grammar. 4. (2 points) Show that your extended grammar can derive the following sentences: ab/ca/bc 5. (3 points) Modify the above grammar by adding the equality operator (==) with the lowest precedence of all operators in the grammar and is left associative