Solution:

To find the pattern in a row of items, we can say the items out loud one by one. Let's try this method together!

1. Strawberry, apple, banana, banana; strawberry, apple, banana, banana. The fruits that comes next will follow this pattern. So we should place an apple and a banana in the empty spaces.
2. Heart, star, star, heart. What should come next? We can use the exclusion method. If the core was a heart and a star, the 3rd item should've been a heart. So it's not correct. If the core was a heart and 2 stars, the 4th item counting from the back should've been a star. So it's not correct either. If the core was a heart, two stars, and a heart, the pattern would work: heart, star, star, heart; heart, star, star, heart; heart, star, star, heart! We found the core of the pattern! Fill in the 1st, 2nd, and 3rd empty spaces with a heart, a star, and a heart, respectively.
3. Use the same method in the previous question. Place a big milk carton and a small milk carton in the 2 empty spaces, respectively.

Solution:

To look for the pattern in a circle, we can start wherever we want. Start with any item and stop before that item appears again, then we get a pattern! For example, if we start with the red gem, there are red, green, yellow, blue, and another red gem. So red, green, yellow, and blue is the core of this pattern. From left to right, we should place a green gem, a yellow gem, and a red gem in the empty spaces.