Earthquakes and volcanoes most commonly occur around plate boundaries because of the movement from the plate boundaries. The interactions between the plates by moving under, upon, or sliding against other boundaries may cause earthquakes and volcanoes.
Answer:
density describes how much space an object or substance takes up (its volume) in relation to the amount of matter in that object or substance (its
mass). In maths and physics density is calculated as mass defined as mass divided by volume (Density = Mass ÷ Volume).
Answer:
48 hours
Explanation:
Using the formula,
R/R' = 2ᵃ/ᵇ..................... Equation 1
Where R = Original amount, R' = Radioactive remain, a = Total time, b = half life.
Given: b = 24 hours,
Let: R = X, then R' = X/4.
Substitute into equation 1
X/(X/4) = 2ᵃ/²⁴
4 = 2ᵃ/²⁴
2² = 2ᵃ/²⁴
Equating the base and solving for a
2 = a/24
a = 24×2
a = 48 hours.
Hence the time = 48 hours
