Answer:

Step-by-step explanation:
we are given half-life of PO-210 and the initial mass
we want to figure out the remaining mass <u>after</u><u> </u><u>4</u><u>2</u><u>0</u><u> </u><u>days</u><u> </u>
in order to solve so we can consider the half-life formula given by

where:
- f(t) is the remaining quantity of a substance after time t has elapsed.
- a is the initial quantity of this substance.
- T is the half-life
since it halves every 140 days our T is 140 and t is 420. as the initial mass of the sample is 5 our a is 5
thus substitute:

reduce fraction:

By using calculator we acquire:

hence, the remaining sample after 420 days is 0.625 kg
Answer:
x = 24
Step-by-step explanation:
x +
x = 36
Make the denominator the same by multiplying the first fraction by 2 to make both denominators 6.
x +
x = 36
Now we can calculate the numerators and keep the denominators the same.
x = 36
Find x.
x =
× 36
x = 24
Answer:
12.6
Step-by-step explanation:
To find the area of a cylinder, you find the area of the circular base and multiply it by the height. Remember that the area of a circle is pi*r^2. R, the radius, is 2. Putting this into a calculator and rounding to the nearest tenth, you get 12.6. Now that we have the circle, we multiply by the height. Since the height is 1, we have our answer of 12.6.
Answer:
4 units i think
Step-by-step explanation:
i dont know how beacuse 4 is answer