Answer:
1. true 2. true 3.true 4. false 5. false
Step-by-step explanation: 4/4-3/4 is 1/5. You multiply the top first (4-3=1) and the bottom isn't supposed to change. so the answer is 1/4
Answer:
16.07 milligrams
Step-by-step explanation:
From the question,
Using the formula of radioactive decay,
R/R' = 2ᵃ/ᵇ..................... Equation 1
Where R = Original mass of the polonium-210, R' = Final mass of polonium-210 after decaying, a = Total disintegration time, b = half life of polonium-210.
Make R' the subject of the equation
R' = R/(2ᵃ/ᵇ)................ Equation 2
Given: R = 100 milligrams, a = 1 years = 365 days, b = 138.39 days
Substitute these values into equation 2
R' = 100/(2³⁶⁵⁰⁰/¹³⁸³⁹)
R' = 100/(6.222)
R' = 16.07 milligrams of plonium-210
B.) 10:18 and 25:45
You can simplify this.
Divide the first part by 2.
5:9.
Divide the second half by 5.
5:9.
5:9 and 5:9