Part a
Answer: 17.58 km/h

Total Distance =10 km
Total time =0.5689 h

Part b
Answer: 17.626 km/h

Total Distance =42.195 km
Total time =2.3939 h

Answer:
88.2 C
Explanation:
The current can be defined as the rate of flow of charge in a conductor.
The relation between charge current and time is given as
I = Q/T
I = current, Q= charge and T = time
that is ampere = coulomb / second
The amount of charge passed is from the negative to the positive terminal
shall be given by:
Q = I * t = 3.5mA * 7h * 3600s/h = 88.2 C
Note: take care of the units.
Answer:
67
Explanation:
- The atomic number (Z) of an atom is equal to the number of protons in the nucleus
- The mass number (A) of an atom is equal to the sum of protons and neutrons in the nucleus
Therefore, calling p the number of protons and n the number of neutrons, for element X we have:
Z = p = 23
A = p + n = 90
Substituting p=23 into the second equation, we find the number of neutrons:
n = 90 - p = 90 - 23 = 67