Answer:
A
Explanation:
Resistors in series add. There is only one path the current can take. That's why Christmas Tree lights sometimes give a lot of trouble. If a bulb burns out, it could be any one of them and time is needed to find the burned out bulb.
That being the case R = R1 + R2
R1 = 50 ohms
R2 = 50 ohms
R = 50 + 50
R = 100 ohms
Answer A
Answer: The atomic mass of a Europium atom is 151.96445 amu.
From the given information:
Percent intensity is 91.61% of Europium atom of molecular weight 150.91986 amu.
Percent intensity is 100.00% of Europium atom of molecular weight 152.92138 amu.
Abundance of Eu-151 atom:

Abundance of Eu-153 atom:

Atomic mass of Europium atom:

Therefore, the atomic mass of a Europium atom is 151.96445 amu.
Answer:
Filtration is a method for separating an insoluble solid from a liquid. When a mixture of sand and water is filtered: the sand stays behind in the filter paper (it becomes the residue ) the water passes through the filter paper (it becomes the filtrate )
Explanation:
Listo!
Answer:
F = 37.8 × 10^(6) N
Explanation:
The charges are 0.06 C and 0.07 C.
Thus;
Charge 1; q1 = 0.06 C
Charge 2; q2 = 0.07 C
Distance between them; r = 3 m
Formula for the force in between them is;
F = kq1•q2/r²
Where k is a constant = 9 × 10^(9) N.m²/C²
Thus;
F = (9 × 10^(9) × 0.06 × 0.07)/3²
F = 37.8 × 10^(6) N
I believe it is A :) hope this helped