The formula for half-life is:

Where A is the amount of iodine-131 initially and after 40 days, t is time, h is half-life of the isotope. Let's plug in our values to the equation:

Therefore, the patient has 0.625 grams of iodine-131 after 40 days.
Answer:

Explanation:
given,
total deflection = 4.12 cm
Electric field = 1.1 ×10³ V/m
plate length = 6 cm
distance between them = 12 cm
using formula

q = 1.6 × 10⁻¹⁹ C
m = 9.11 x 10⁻³¹ kg
d = 0.06 m
L = 0.12 m

v_0 = 6496355.63 m/s




Im sorry may you please retake the picture then i will answer
The two subatomic particles that contribute to the net charge of an ion are electrons and protons.
<h3>What is an atom?</h3>
Atom is the smallest possible amount of matter which still retains its identity as a chemical element, now known to consist of a nucleus surrounded by electrons.
The atom is made up of three components called subatomic particles as follows;
The proton is the positively charged subatomic particle forming part of the nucleus of an atomwhile the electron is the subatomic particle having a negative charge and orbiting the nucleus.
This suggests that the two subatomic particles that contribute to the net charge of an ion are electrons and protons. That is;
Net charge = protons - electrons
Learn more about subatomic particles at:brainly.com/question/13303285
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