A = -9.8
v = -9.8t -8
s = -4.9 t2 -8t +25
So… -5t^2 -8t + 25 =0, we’ll rearrange to 5t^2 + 8t - 25. We get two roots, one is positive and is 1.59 seconds
V = -9.8(1.59) - 8 = -23.6
So… it takes 1.59 seconds to hit the ground at -23.6 m/s.
Answer:
All the elements of a period have similar chemical properties because they have the same number of valence electrons in their outermost shell. Their atoms have the same number of electrons in the highest occupied energy level
Answer
D) burning a candle
Explanation
When burning a candle no new substance is form.
We have both physical and chemical change occuring.
Physical part: Melting of the solid wax and evaporation of the liquid forms the physical change.
Chemical part: burning of the wax vapour forms the chemical change.
When rain falls on the land, it either seeps into the ground or becomes runoff, which flows downhill into rivers and lakes.