Answer:
The focal length of a lens is refers to the distance from the center of the lens to the principal foci.
11.1 m/s
Explanation:
120 km = 120 x 1,000 = 120,000 m
3 hours = 3 x 60 x 60 = 3600 x 3 = 10,800 s
speed = 120,000 / 10,800
= 1200/108
= 11.1 m/s
2 sig
1 and 7
Yes
Li+ [He]
N³- [Ne]
In³+ [Kr] 4d10
Tl+ [Xe] 4f14 5d10 6S2
