4) Students in Ms. Arnic’s science class planted 13 conifers in different places around the school yard. They measured the heights (in inches) of the conifers one month after planting them. How many conifers are greater than 6 1/4 inches tall but less than 8 1/2 inches tall?

I need more information in order to answer that question, such as the heights of the conifers.