Mechanical energy (ME) is the sum of potential energy (PE) and kinetic energy (KE). When the toy falls, energy is converted from PE to KE, but by conservation of energy, ME (and therefore PE+KE) will remain the same.
Therefore, ME at 0.500 m is the same as ME at 0.830 m (the starting point). It's easier to calculate ME at the starting point because its just PE we need to worry about (but if we wanted to we could calculate the instantaneous PE and KE at 0.500 m too and add them to get the same answer).
At the start:
ME = PE = mgh
ME = 0.900 (9.8) (0.830)
ME = 7.32 J
I believe that the statement above is TRUE. I can say that it's true because based on the definition of what reciprocal liking is, this is the probability of having to like someone who also likes them in return. Therefore, if they like each other, this means that there is a low risk of rejection in the relationship.
The Answer is C. the distance light travels in a year