You know that as we go higher than the sea level, the boiling point of water decreases. What would be the effect on the melting point of solid?

Explanation

iii . a. With increased height from sea level, i.e., at high altitudes atmospheric pressure decreases, causing melting point of solids that expand on solidifying (ice) to increase.
b. If the solid contracts on solidifying, then low pressure at high altitude causes its melting point to lower.