SA = 1,226 in.² (Hope this helps!)
To find the circumference of a circle that lists only as a diameter, you would do pi*d so lets say the diameter is 6, you would do pi*6 which would end up giving you 18.84. I hope this helps a bit! (:
= 18 1/5 + 22 2/5 + 40 1/5
answer is D. last one
Step-by-step explanation:
Option C
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
