Introduction:
The tree in hilly areas is a unique ecosystem that adapts to the specific conditions of hilly terrain. These trees have certain characteristics that help them thrive in these environments. This response will discuss the statements given in the question and explain why each statement is true.

Explanation:

Statement a) These trees are normally cone shaped:
- One of the characteristics of trees in hilly areas is their cone-shaped structure. This shape helps the trees withstand strong winds that are often present in hilly regions.
- The cone-shaped structure of these trees allows wind to pass through them easily, reducing the risk of branches breaking or the entire tree toppling over.
- Additionally, the cone shape helps the tree shed snow more easily, preventing excess weight on the branches that could cause them to snap.

Statement b) They have sloping branches:
- Sloping branches are another adaptation of trees in hilly areas.
- Sloping branches help the tree withstand heavy snowfall. When snow accumulates on the branches, the sloping shape allows the snow to slide off more easily, preventing the branches from breaking under the weight.
- This adaptation is essential for the survival of these trees in regions with frequent snowfall.

Statement c) The leaves of some of these trees are needle-like:
- Many trees in hilly areas have needle-like leaves.
- Needle-like leaves have several advantages in hilly environments. They often have a waxy coating that helps reduce water loss through evaporation, allowing the tree to conserve water in dry and windy conditions.
- The needle-like leaves also minimize the surface area exposed to the wind, reducing the risk of excessive moisture loss.
- Furthermore, needle-like leaves are better adapted for shedding snow, as the narrow shape prevents snow from accumulating and weighing down the branches.

Conclusion:
In conclusion, all the statements given in the question are true. The tree in hilly areas is cone-shaped, has sloping branches, and some of these trees have needle-like leaves. These characteristics are adaptations that help the trees survive in the challenging conditions of hilly regions, including strong winds, heavy snowfall, and dry environments.