Greek Pasta Salad I

This is a great make-ahead pasta salad!
Ingredients
• ½ cup olive oil
• ½ cup red wine vinegar
• 1 ½ teaspoons garlic powder
• 1 ½ teaspoons dried basil
• 1 ½ teaspoons dried oregano
• ¾ teaspoon ground black pepper
• ¾ teaspoon white sugar
• 2 ½ cups cooked elbow macaroni
• 3 cups fresh sliced mushrooms
• 15 cherry tomatoes, halved
• 1 cup sliced red bell peppers
• ¾ cup crumbled feta cheese
• ½ cup chopped green onions
• 1 (4 ounce) can whole black olives
• ¾ cup sliced pepperoni sausage, cut into strips