Answer:
The speed is 0.97 c.
Explanation:
Given that,
Dilated time t'= 50.0 years
Rest time t = 13.0 years
We need to calculate the speed
Using formula of time dilation

Where, t' = change in time
t = rest time
v = velocity
c = speed of light
Put the value into the formula




Hence, The speed is 0.97 c.
The answer is B) i am 100% positive
I- wym incorrect answer i-
B. They came up with the term “radioactivity.”
C. They conducted experiments with uranium-containing minerals and pure uranium.
E. They discovered two new radioactive elements
Mechanical energy
I think