Answer:
1. Option D. 1.86x10^19 electrons.
2. Option B. 4.0x10^–16C.
Step-by-step explanation:
1. Determination of the number of electrons in – 3C.
This can be obtained as follow:
–1C = 6.2x10^18 electrons
Therefore, –3C = –3C/–1C x 6.2x10^18 electrons = 1.86x10^19 electrons.
Therefore, there are 1.86x10^19 electrons in –3C.
2. Determination of the number of coulomb in +2500e.
This can be obtained as follow:
1e = 1.602176x10^–19C
Therefore, 2500e =
2500 x 1.602176x10^–19 = 4.0x10^–16C
Therefore, 2500e contains 4.0x10^–16C