Answer:
U shaped vallies?
Explanation:
(i dont know if this was one of the options)
1. Antelope Canyon was formed by the erosion of Navajo Sandstone.
2. The appearance of water is determined
by the way the water molecules are moving.
3. Moist rising air near the Equator cools and condenses into clouds and, later, rain.
The given chemical equation is:

On balancing the equation we get,

Calculating enthalpy of formation of this reaction from the standard heats of formation of the products and reactants:
Δ![H_{reaction}^{0}=[H_{f}^{0}(Al_{2}O_{3}(s)) + (3*H_{f}^{0}(H_{2}SO_{4}(aq))] - [H_{f}^{0}(Al_{2}SO_{4}(aq)) + (3*H_{f}^{0}(H_{2}O(l))]](https://tex.z-dn.net/?f=H_%7Breaction%7D%5E%7B0%7D%3C%2Fp%3E%3Cp%3E%3D%5BH_%7Bf%7D%5E%7B0%7D%28Al_%7B2%7DO_%7B3%7D%28s%29%29%20%2B%20%283%2AH_%7Bf%7D%5E%7B0%7D%28H_%7B2%7DSO_%7B4%7D%28aq%29%29%5D%20-%20%20%20%5BH_%7Bf%7D%5E%7B0%7D%28Al_%7B2%7DSO_%7B4%7D%28aq%29%29%20%2B%20%283%2AH_%7Bf%7D%5E%7B0%7D%28H_%7B2%7DO%28l%29%29%5D)
=[(-1669.8kJ/mol)+ {3* (-909.27 kJ/mol)}]-[(-3442kJ/mol)+{3*(-285.8 kJ/mol)}]
=[(-4397.61kJ/mol)]-[(-4299.4kJ/mol)]
=-98.21kJ/mol
Total enthalpy change when 15 mol of
reacts will be=

In the reduction-oxidation reaction given, Cu is reduced because it gained 2 electrons, on the other hand H2 is oxidized because it gained one electron. I hope this helps.