Answer:
option (c) is correct
Explanation:
Half life of a substance is the time in which the element becomes half of is initial value.
half life, T = 8 days
Amount remaining, N = 10 % of original value
Let the original value is No.
N = 10% of No
N = 0.1 No
Let the time taken is t and the decay constant is λ.
The relation between the decay constant and the half life is given by

Us the equation of radioactivity



Taking natural log on both the sides, we get
0.08664 t = 2.303
t = 26.6 days
D. to be structural material
Answer:
Complete Circuit
Explanation:
A circuit is defined as a completed path for voltage to flow from a source of voltage through a load and back to the source. A complete circuit or path is often referred to as a(n) ? circuit. Before current can flow in a circuit, the circuit must be closed. 100% right
That is because there are other forces like the friction forces that apply differently on both of them. The frictional forces applied to the sled are smaller than they are on the father, for example, so it's possible for him to pull it.
The correct answer is b , the the liquid with heat and cool faster