Answer:
Explanation:
I will GUESS that we're supposed to be looking at a plot of a position in time.
IF that is the case.
THEN the answer would be Point B because it has the steepest slope.
Engineers have designed experimental cars that use liquid hydrogen for fuel instead of gasoline. this is an example of Substitution.
Substitution is the process where one thing replaces other for a particular purpose. here liquid hydrogen is replacing the gasoline for fuel in car. hence the correct word to fill is Substitution.
Answer:

Explanation:
It is given that,
Initially, the electron is in n = 7 energy level. When it relaxes to a lower energy level, emitting light of 397 nm. We need to find the value of n for the level to which the electron relaxed. It can be calculate using the formula as :


R = Rydberg constant, 

Solving above equation we get the value of final n is,

or

So, it will relax in the n = 2. Hence, this is the required solution.
Answer:
Explanation:
Let the forward displacement is taken is positive, and the backward displacement is taken is negative.
first displacement = + 18 cm
second displacement = - 6 cm
third displacement = - 12 cm
net displacement = 18 - 12 - 6 = 0 cm
Believe it or not white clouds can be both opaque and transparent depending on the volume and mass within that cloud. The heavier the cloud, the more opaque it'll seem, but the lighter the cloud is, it'll seem transparent-