Who is Dede and what are her symptoms. We need more context
The type of stream valley likely to form in a mountainous area is a V- shaped valley. This is a narrow valley that has a profile giving the impression of the letter V. This kind of valley is characterized by steeply sloping sides. It results from a stream eroding downward, a process referred to as downcutting. V - shaped valleys form in mountains or highland areas where streams are in their youthful stage and are flowing rapidly down steep slopes.
Because when baking soda react with vinegar It will produce CO2 which is phase gas ..And this CO2 will evaporate
NaHCO3(s) + CH3COOH(aq) → CH3COONA(aq) + CO2(g) + H2O(l)
so the mass wil decrease because CO2 will evaporate
D.) Fossils. Fossils are skeletons of creatures that lived in the past.
