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
X=8.5 because angle B and angle D are congruent using alternate interior angles theorem. so you would find the measure of B by adding 50+45 to get 95, then subtract 95 from 180 to get 85 degrees for angle B. Now your equation is 10x=85 so if you divide 85/10 you get x=8.5! hope this helped :)
It should be D.
“Mr. Roberts drive five miles more than half the distance he drove on Monday”
Five miles more is key here
This says that he drove five more after dividing it, so 42/2 first than add the 5
Answer:
it A
Step-by-step explanation:
tan c=opp c/adj c
tan c=7/16
tan c=0.44