Ah, yes
if you start with P amount of something and the half life is h units (in years) and the time elapsed is t (in years) then the amount left is A
the equation is

so
given
h=1620
P=150
t=200
so


use your calculator
A≈137.69781917515g
about 138grams left

The ball reaches its maximum height after 3.5 seconds, and the maximum height is 61.025 meters.
Answer:
520 out of 800 students ride the bus
Step-by-step explanation:
Given


Required
Determine the number of students 
To do this, we simply multiply the proportion by the total number of students.
i.e.


Express the percentage as decimal


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Answer:
He had been in a hospital with friends since his birth
Answer:


Step-by-step explanation:
considering the equation

solving






solving





also solving





Therefore,

